Making category sort keys work for blog posts

As of now, categories are using hardcoded sorting, ordered by username and blog title. This change allows custom sort keys added using {{DEFAULTSORT:sortkey}} or [[Category:Categoryname|sortkey]].
Update CategoryViewer::addPage hook handler in Answers

The changes made to the CategoryViewer::addPage hook in VOLDEV-29 necessitate an update of its handler answerAddCategoryPage in Answers.php so that it can process the extra parameter (string $humanSortkey).
Special:Connect - no more accounts without email
Added trim() for validated fields
add article type indexer
PLA-1061 null was casted to int
PLA-766 PLA-1123 filtering out noncommercial wikis
PLA-766 PLA-1123 optimizing
Added first version of CheckFounders.php maintenance script - getting recent founders list
added constants and exit() calls, added method to check recent founders in wikicity.user table
added two more exit codes, usage of $wgExternalSharedDB, updated documentation
added reporting "invalid founders" via Wikia::log with "MOLI:" label
docs updated, used right global var
CONN-293 - UTF-8 Whitespace in title breaks the modal
CONN-295 - Error message shown on long non-latin title
addressed CR notes: used PHP_EOL and split one string
addressed CR notes: added a constant with log label
addressed CR notes: removed unnecessary rtrim()
addressed CR notes: removed unnecessary else
addressed CR notes: new line at the EOF
addressed code review notes: removed getDates() function and used DatabaseBase::timestamp() method to get start and end dates