Bump version for 2.12.x

For this step, we still depend on _2.11 libraries (partest, xml,
parser-combinators).

After we release the first milestone of 2.12, we will update
versions.property to bootstrap to 2.12 dependencies.
Disable MiMa on the 2.12.x branch
Merge pull request #3715 from retronym/topic/bump

Bump version for 2.12.x
Merge remote-tracking branch 'origin/2.11.x' into merge/2.11.x-to-2.12.x
@inline Predef.identity[A].

Since identity[A] is often used as a function directly supplied to
methods requiring (A)=>A, there's no need to have the generated
Function1 object contain an explicit call to identity[A]().

This implementation isn't going to change, so let the synthetic
Function1 elide the extra call, generating just "aload_1; areturn".
Make PartialFunction.OrElse extend AbstractPartialFunction.

This shaves a few kB off of the generated class file.
Merge remote-tracking branch 'origin/2.11.x' into merge/2.11.x-to-2.12.x
Merge pull request #3731 from retronym/merge/2.11.x-to-2.12.x

Merge 2.11.x to 2.12.x
Merge pull request #3740 from tvierling/trait-instantiation

Make PartialFunction.OrElse extend AbstractPartialFunction.
Deprecation of @BeanInfo
Merge pull request #3737 from tvierling/identity-inline

@inline Predef.identity[A].
Merge pull request #3746 from lrytz/beanInfoDep

Deprecation of @BeanInfo
Merge branch '2.11.x' into 2.12.x
Merge pull request #3773 from lrytz/merge-2.12

Merge 2.11.x into 2.12.x
Make comment consistent with code
Merge commit '9e79885' into merge-211
Merge commit 'e948b39' into merge-211
Merge branch '2.11.x' into merge-211
Merge pull request #3808 from lrytz/merge-211

Merge 2.11.x into 2.12.x
Update AnyVals.scala

Corrected api doc for >> operator to say it bit-shifts right rather than left, and fills the left bits rather than the right bit