Add basic support for the priority rules prefix. This patch does not
allow the utils to set or suggest priorities. It allows parsing and
retaining of the priority prefix if it already exists on rules and
checking if it's in the supported range.
Signed-off-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
These two classes are meant to handle the definition of boolean rules
like `$foo = true`.
Also extend RE_PROFILE_BOOLEAN to provide named matches.
As usual, add tests for the new classes.
