Fixing feedback's view when assignment is set to no grade. Also refactoring the use of method view_feedback for upload (single and advenced) assignments

Conflicts:

	mod/assignment/type/upload/assignment.class.php
	mod/assignment/type/uploadsingle/assignment.class.php
MDL-29689 Assignment 2.2: A student can see feedback for assignments with no-grades
MDL-29689 Assignment 2.2: cleaned print_responsefiles function
MDL-35787 Mnet: fixed php strict standards warnings
MDL-35787 Mnet: If student role is not defined then throw error
MDL-35571 theme_magazine: RTL fixes - WIKI title headings, ajax frontpage category/course chooser, right align logo, left align course name, left align login & user info.
MDL-35469 fix Gecko based browser checks

The problem is that latest firefox versions stopped using dates because they lost the meaning over the time.
MDL-35469 test for the new Gecko user agent handling
MDL-33621 rating: fixed view help error for global scale rating
MDL-31629 auth_shibboleth Use correct language string location
MDL-31824 - Calendar - Fixing HTML classes fopr calendar month view - patch provided by Mark Ward
MDL-35510 theme_mymobile: RTL fixes for course and category names in style/jmobile11_rtl.css
MDL-25290 conversion: Converted string cache to MUC
MDL-21625 Question bank: Add accessibility to table layout for viewing question list
MDL-36107 scorm: Fix non-static method call
MDL-21625 Question bank: fixing whitespace
MDL-35249 - Move Grading popmenu "userid" column after "scale" column (workaround)
MDL-36142 Incorrect SQL query (wrong usare of quotes) returns HTTP 404 due to a dml_read_exception
MDL-35771 lower the index values in file related code to prevent dragging problems in YUI
MDL-34530 Calendar: Can create event for any group, but cannot view it