.cache/ Invalidation

[euisuny]

Invalidate the .cache/ generated by ParcelJS whenever the compiler is updated/rebuilt.

[Checkmate50]

We discussed this a while back -- at the time, we said it was unnecessary since it doesn't effect the end user since they won't be rebuilding the compiler

[euisuny]

It's becoming kind of frustrating during development, this could just be an extra line in our Makefile when we build our compiler that removes the .cache folder.

[sampsyo]

This issue seems relevant: parcel-bundler/parcel#729

[bionicles]

this fix would be great!