Prepare for 4.0.0-rc1
Adds eclipse platform in IDE build UID

It is required to be able to use the cache and make a difference
between builds for kepler and luna
Remove accidental additions that caused the PR validator for Scala to fail.
Merge pull request #61 from dragos/issue/fix-pr-validator

Remove accidental additions that caused the PR validator for Scala to fail
Downgrade to 0.13.5 for PR-validations sake.
Merge pull request #62 from dragos/master

Downgrade to 0.13.5 for PR-validations sake.
Merge pull request #60 from skyluc/pretag/4.0.0-rc1

Pretag/4.0.0 rc1
Revert "Merge pull request #59 from huitseeker/pr-scala-resolver"

This reverts commit 1c313796ff14c756135912c671dd013ad7d552b1, reversing
changes made to 5aa00b1d8999f553c276f5e830fecf9831d0ee03.
Revert "Merge pull request #58 from huitseeker/update-sbt-0.13.6"

This reverts commit 5aa00b1d8999f553c276f5e830fecf9831d0ee03, reversing
changes made to 9037d7359cdc06b5de77a245ca5c581f74016039.
bump sbt versions to 0.13.5