(bug 32774) Added config options and flags for SSL and compression in DB.

(bug 32774) Added config options and flags for SSL and compression in DB.

Added configuration options ($wgDBssl, $wgDBcompress) and related
connection flags (DBO_SSL, DBO_COMPRESS) to allow SSL/TLS and
compression on database connections. The flags are only observed if
the functionality is supported for that type of database (e.g.,
SQLite will ignore both flags as neither are supported).

Currently, only MySQL and PgSQL have support for at least one of
these flags in their PHP extensions. MySQL supports both flags and
PgSQL supports the SSL flag only.

Change-Id: I7b4d3ba82ccab0eed4a19e3b4e7bc0b4eb881262
Signed-off-by: Tyler Anthony Romeo <tylerromeo@gmail.com>