WAMR-04-15-2021

Re-org fast-interpreter to support unaligned address access for some CPUs
Implement auxiliary stack overflow/underflow check for AOT/JIT/interpreter
Enable SIMD128 feature for AARCH64 target
Implement realloc wrapper in builtin libc
Update sample workload's scripts to align with latest emcc
Fix aot code failed to run on darwin/android issue
Fix aux stack overwritten issue when lib-pthread is enabled
Fix pthread_join overwrite issue when lib-pthread is enabled
Fix compile warnings on windows platform: dll linkage and others
Fix llvm target vendor-sys-abi not correctly set issue on windows platform