MDL-44015: EditPDF scrolls instead of drawing on iOS
MDL-46496 JS: Replace jQuery UI 1.10.3 minified CSS

The original version contained some invalid paths for images. I'm unsure
where these came from as the version from the offical jQuery UI does not
contain these, and these were the only differences in the files.
MDL-30668 gradereport_grader: split user preferences into individual courses

This solves the DB exception when users were trying to insert very large string in DB
MDL-46688 weblib: improve the highlight function.

Thanks to Joseph Baxter for suggesting some of the test cases.
MDL-35984 grade: Add behat tests for grade aggregations
MDL-35984 grade: Recalculate min/max for sum of grades when hidden grades are involved.
MDL-35984 Grades: Fix deprecation of grade_category::aggregate_values
Merge branch 'wip-MDL-30668-m26' of git://github.com/marinaglancy/moodle into MOODLE_26_STABLE
Merge branch 'MDL-46688_26' of git://github.com/timhunt/moodle into MOODLE_26_STABLE
Merge branch 'm26_MDL-44015' of https://github.com/greg-or/moodle-mod_assign into MOODLE_26_STABLE
Merge branch 'MDL-46496-26' of git://github.com/andrewnicols/moodle into MOODLE_26_STABLE