Exclude current user from user options when sending PM

[rica-carv]

Motivation and Context

The current code for the form userlist DON'T excludes current user even if the trigger 'excludeSelf' is true.
Ie: this line userlist('pm_to',null,array('excludeSelf'=>true, 'default'=>'blank', 'classes'=>varset($this->pmPrefs['send_to_class'], e_UC_MEMBER))) would ALWAYS give the list INCLUNDING current user...
Issue is visible when trying to send a PM to another user

Description

Added code line to exclude current user if trigger is set

How Has This Been Tested?

Tested on latest e107 from github

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (a change to man pages or other documentation)

Checklist

• My code adheres to the e107 code style standard.
• [ x I have read the contributing document.
• I have added tests to cover my changes.
• All new and existing tests pass.