* crizz0/ticket/9758:
[ticket/9758] Clickable avatar in header and renamed class for avatar-img
[ticket/9758] Remove unnessary if-question for include functions_display
[ticket/9758] Slims the line 4775 in includes/functions.php
[ticket/9758] Adds id and changes filter to fix travis CI test
[ticket/9758] Removed the needless space after first ENDIF
[ticket/9758] Adding impr. for overall_header display of avatar and username
[ticket/9758] Fixed bug in mcp_warn.php
[ticket/9758] Optimises the html code of avatar image in header
[ticket/9758] Error because of missing functions_display.php fixed
[ticket/9758] Removed useless if-conditions to include functions.php
[ticket/9758] Changes class name of new "span" in overall_header.html
[ticket/9758] Adds global template variable CURRENT_USER_AVATAR