Summary:
Some times chrome caches the output from metro bundler, meaning when developing, it uses old source files and your changes have no effect.
This fixes that by adding dont-cache to the headers of all files served.
Reviewed By: danielbuechele
Differential Revision: D12922357
fbshipit-source-id: 2c3bdf8fb60e4ec64ace2c21f6b1e4656f885339