Support regular expressions for ref access rules

This change considers the rights of the most specific ref pattern.
If the ref pattern starts with ^ it is considered to be a regular
expression, otherwise the older glob style or exact match rules
are used.

Change-Id: Ie060d3758e5184a7cedd38883253f60817a04e1b
Portions-by: carloseduardo.baldacin <carloseduardo.baldacin@sonyericsson.com>
Signed-off-by: Shawn O. Pearce <sop@google.com>
9 files changed