Bump version for 0.13.7-RC1
Add warning about incompatible parser.
Fix markdown for code example.
Fix the run logic so the mainClass setting is actually used when set.
Add automated tests for main-class regression.
Fix BC issue discovered in #1696.

Def.derive has a new parameter, so we add an override which delegates down to the new method.
Merge pull request #1694 from sbt/wip/mainClassBreakage

Fix the run logic so the mainClass setting is actually used when set.
Fixes #1699. ignore transitive force during cached resolution

When Ivy translates pom to ivy.xml, it adds force=“true”.
So when both non-Maven dependencies and Maven dependencies are mixed, Maven dependencies always wins, which is the case for scala-library dependency added by the user.
Merge pull request #1698 from sbt/wip/bc-regression

Fix BC issue discovered in #1696.
modify test that test transitive force

This test relies on force having effect transitively for cached
resolution.
added comments
Merge pull request #1700 from sbt/fix/1699

Fixes #1699. ignore transitive force during cached resolution
Bump RC version for release.
Reset sbt version after merge.
Merge pull request #1703 from sbt/wip/merge-0.13.7

Wip/merge 0.13.7