MDL-35979 - Commenting - Adding an empty alt attribute to the javascript generated delete icon for comments
MDL-36490 theme_standard: reduces the 15px radius down to 3px in style/css3.css for .generalbox objects
MDL-29733 grade: Query for Identifying Grade Grades to Precreate is SLOW
MDL-29733 grade: SQL and comment cleanup
MDL-32639 files: Removing '0' start folder in archives created with filemanager

Signed-off-by: Vadim Dvorovenko <vadimon@mail.ru>

Conflicts:

	lib/filestorage/zip_archive.php
MDL-32639 files: Improved File Manager download and zip support

Conflicts:

	lib/filestorage/zip_packer.php
MDL-32639 files: Zipping a folder does not overwrite existing files
MDL-37014 repository_webdav - strip the server URL from file & folder paths returned by webdav lib (if present)
MDL-37078: Restore - section restore fails with multiple availability conditions
MDL-35056 - Backup/Restore - Converting the 'Unmet Dependencies' Message to be a Developer Debug message to make moodle less confusing to the average user
MDL-35874 - Blocks - Adding a label to the 'Add a block' block's select field
MDL-36456 repository: S3 handles errors in a nicer way
MDL-37176 timezones: updated to 2012j
MDL-36597 strip '_utf8' from all course.lang fields
MDL-37111 copy first post files in single type forum using intro options

This patch also removed the delete button from the first post in single
discussion type forum.

Edit button in the first post leads to the forum edit page now, this should
prevent other problems throwing first post and intro out of sync.
MDL-36493 improve performance of mysql unsigned/lob upgrade
MDL-36493 improve timeout handling in mysql upgrade

Credit goes to Mark Nielsen, thanks.
MDL-36475 tweak zIndexes once more

The expected ranges are now:
* 0-1000 for normal code
* 5000-5999 for TinyMCE
* 7000-8999 for filepicker and filemanager

This patch fixes also incorrect location of "MDL-25736 - French spellchecker fixes." modification reminder.
MDL-36245 try to workaround buggy iconv() when converting text from utf-8 to utf-8
MDL-36245 add tests for the buggy utf-8 to utf-8 conversion