[analyzer] RetainCount: Add a suppression for "the Matching rule".

In the OSObject universe there appears to be another slightly popular contract,
apart from "create" and "get", which is "matching". It optionally consumes
a "table" parameter and if a table is passed, it fills in the table and
returns it at +0; otherwise, it creates a new table, fills it in and
returns it at +1.

For now suppress false positives by doing a conservative escape on all functions
that end with "Matching", which is the naming convention that seems to be
followed by all such methods.

Differential Revision: https://reviews.llvm.org/D61161

llvm-svn: 359264