Merge 2.10.x

Patches applied:
 - rename of `dropRepeatedParamType` to `dropIllegalStarTypes` -- required since 8886d22
 - fixed test/files/neg/t6406-regextract.flags -- how could this have worked before?

Conflicts:
	src/compiler/scala/tools/nsc/interpreter/TypeStrings.scala
	src/library/scala/collection/LinearSeqOptimized.scala
	src/library/scala/util/Properties.scala
	test/files/run/streams.check
	test/files/run/streams.scala

review by @paulp