#4 Suport regexp/wildcards rules for priority

[gcb]

Now suports <pfilter> tags. They work just like the
<filter> one but instead of the action attribute they
use a priority attribute to set a predefine value to
the urls matching the rule, so you don't have to
manualy specify each url priority.

your config file can look like:
<filter action="drop" type="wildcard" pattern="*.jpg*"
/>
<pfilter priority="1" type="wildcard"
pattern="*important*.html" />
<pfilter priority="0.1" type="wildcard"
pattern="*joke*" />