Use binary charset in default table options

Use binary charset in default table options

$wgDBTableOptions is overridden in the installer-generated
LocalSettings.php, and is always set to binary now that the installer UI
option has been removed. However, the value from DefaultSettings.php is
used when the installer installs an extension, since in this case
DatabaseUpdater is called without reading the generated
LocalSettings.php.

Binary is almost certainly the right answer since many extensions can't
even be installed without this option, they hit a key length error.

Change-Id: I87df736a4d9e49c9535d55bd556e636500ca203f