Pre SIP: Demote match keyword to a method

[xuwei-k]

FYI, a long time ago, match was a method of scala.Any.

• https://github.com/scala/scala/blob/d53c0dadb92173a6caeb6a1f31dafa92dcff6833/doc/reference/ReferencePart.tex#L3667-L3702
• https://github.com/scala/scala/blob/d53c0dadb92173a6caeb6a1f31dafa92dcff6833/sources/scala/List.scala#L430

removed 2006 from spec.

• https://github.com/scala/scala-dist/commit/ea2ca174883e872534b6552b8e345b461102c993#diff-31cdb857f2e594d1586116f9f506113aL4766