Fixing bug in participant_delink push
Fixing bug causing incorrect site-restricted lists

When using the "no-site" option the participant_site table was being
joined without restricting by service_id.
Fixing bug in last commit
Renaming alternate type names

Proxy is now Proxy Decision Maker
Informant is now Proxy Information Provider
Adding new method: record::get_distinct_values()

This method returns the distinct values found in a table's column
Adding grouping to participant report
Fixing bug in base_report widget

Grouping restriction wasn't creating the enum list correctly
Adding region to participant status pull operation
Adding HAVING statements to the modifier class
Merge remote branch 'origin/qa' into release
Updating error codes