thought-machine/please v4.0.2

Please v4.0.2

on GitHub

The first public-ready release of the v4 branch is available!

Notable features / changes:

• Some rewrites of Go rules which are now compatible with Go 1.7 and somewhat
  cleaner & faster.
  This means go_binary rules must declare all dependencies used in its main package explicitly;
  previously it was possible to pick them up transitively.
• Config options can be dynamically overridden on the command line,
  e.g. plz build -o go.version:1.7
• Output files are made read-only in most cases.
• Post-build functions are run once only since it's quite tough to require them to be idempotent.
• python_binary now correctly accepts a rule for its main.