Fixed history_6rolls_35bag.lua for real.

[zaphod77]

The following changes have been made.

1. implement updating the 35 bag before each reroll.
2. implement original TI bug that causes the bag to sometimes not update when it was clearly intended.
3. implemented original fallthrough logic with rerolls. Should the PRNG ever get changed to the one that TGM games other than TGM4 use, this may actually matter. For now it doesn't.
4. added comments explaining stuff.

Not done:

1. uses actual reroll logic on first piece instead of the existing clever hack
2. change piece ids to be same as TI's.

This has been tested, and feels much closer.

[Tetro48]

hey, use camelCase for function names, snake_case for variable names (even if they are local)

[zaphod77]

okay, i think i have made the required style changes.