Added File.touch, closes #111
Renamed Either.map to Either.bimap [Breaking change]
Added implicit conversion of Either to RightProjection (and back again), closes #139
Merge branch 'master' into 2.9

Conflicts:
	core/src/main/scala/pimpathon/either.scala
	core/src/main/scala/pimpathon/file.scala
	core/src/test/scala/pimpathon/either.scala
	core/src/test/scala/pimpathon/util.scala