refactor: fix warning: lifetime flowing from input to output with different syntax can be confusing

[kanarus]

Fixing warnings generated by current nio v0.0.1:

cargo check
warning: lifetime flowing from input to output with different syntax can be confusing
  --> libs/mpmc-channel/src/lib.rs:46:20
   |
46 |     pub fn produce(&self) -> Producer<T> {
   |                    ^^^^^     ----------- the lifetime gets resolved as `'_`
   |                    |
   |                    this lifetime flows to the output
   |
   = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
46 |     pub fn produce(&self) -> Producer<'_, T> {
   |                                       +++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> libs/mpmc-channel/src/lib.rs:55:20
   |
55 |     pub fn consume(&self) -> Consume<T> {
   |                    ^^^^^     ---------- the lifetime gets resolved as `'_`
   |                    |
   |                    this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
55 |     pub fn consume(&self) -> Consume<'_, T> {
   |                                      +++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> libs/mpmc-channel/src/lib.rs:63:24
   |
63 |     pub fn try_produce(&self) -> Result<Producer<T>, WouldBlock> {
   |                        ^^^^^            ----------- the lifetime gets resolved as `'_`
   |                        |
   |                        this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
63 |     pub fn try_produce(&self) -> Result<Producer<'_, T>, WouldBlock> {
   |                                                  +++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> libs/mpmc-channel/src/lib.rs:75:24
   |
75 |     pub fn try_consume(&self) -> Result<Consume<T>, WouldBlock> {
   |                        ^^^^^            ---------- the lifetime gets resolved as `'_`
   |                        |
   |                        this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
75 |     pub fn try_consume(&self) -> Result<Consume<'_, T>, WouldBlock> {
   |                                                 +++

warning: `mpmc-channel` (lib) generated 4 warnings
warning: lifetime flowing from input to output with different syntax can be confusing
   --> src/net/tcp/stream.rs:138:18
    |
138 |     pub fn split(&mut self) -> (ReadHalf, WriteHalf) {
    |                  ^^^^^^^^^      --------  --------- the lifetimes get resolved as `'_`
    |                  |              |
    |                  |              the lifetimes get resolved as `'_`
    |                  this lifetime flows to the output
    |
    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
    |
138 |     pub fn split(&mut self) -> (ReadHalf<'_>, WriteHalf<'_>) {
    |                                         ++++           ++++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> src/net/tcp/split.rs:24:22
   |
24 | pub fn split(stream: &mut TcpStream) -> (ReadHalf, WriteHalf) {
   |                      ^^^^^^^^^^^^^^      --------  --------- the lifetimes get resolved as `'_`
   |                      |                   |
   |                      |                   the lifetimes get resolved as `'_`
   |                      this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
24 | pub fn split(stream: &mut TcpStream) -> (ReadHalf<'_>, WriteHalf<'_>) {
   |                                                  ++++           ++++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> src/runtime/handle.rs:58:18
   |
58 |     pub fn enter(&self) -> EnterGuard {
   |                  ^^^^^     ---------- the lifetime gets resolved as `'_`
   |                  |
   |                  this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
58 |     pub fn enter(&self) -> EnterGuard<'_> {
   |                                      ++++

warning: lifetime flowing from input to output with different syntax can be confusing
  --> src/runtime/multithread/mod.rs:73:18
   |
73 |     pub fn enter(&self) -> EnterGuard {
   |                  ^^^^^     ---------- the lifetime gets resolved as `'_`
   |                  |
   |                  this lifetime flows to the output
   |
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
   |
73 |     pub fn enter(&self) -> EnterGuard<'_> {
   |                                      ++++

warning: `nio` (lib) generated 4 warnings
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s

[nurmohammed840]

Thanks!

There is a bug in IO (mio) stack, that sometime cause deadlock in test suite (specific), I can't reproduce it,
Current implementation closely followed Tokio implementation of network API. Which may causing that issue.

But in future, I am planning to re-implement network API, which hopefully solve this problem.

Anyways thanks again!