BUG: Fix select from files treedropdown
NEW 'Choose another file' button on upload field AAS-917
Merge pull request #2008 from adrexia/upload-tree

BUG: Fix select from files treedropdown
Merge pull request #2007 from adrexia/extraclass-on-media

BUG: Classes applied to media are too generic to use
Merge pull request #1786 from colymba/3.0-htaccess-fix

vendor folder is blocked only if outside themes
Merge pull request #1760 from jedateach/patch-3

CommandLine: Info about running regular tasks with cron
Update commandline.md
NEW UploadField displays a warning before overwriting files (only relevant if config.yml: Upload:replaceFile = true).
Update commandline.md
Merge commit '22c7bbf' into 3.1
Fixes #1892 - Stop session hijacking with UA check
Merge pull request #2010 from ss23/fix-1892-session

Fix #1892 - Stop session hijacking with UA check
Note for magic quotes change
Check that Webserver is not Apache/1.x in light of installer assets/.htaccess alterations
Merge branch 'hackfest_may_2013' of https://github.com/NightJar/sapphire into 3.1

Conflicts:
	docs/en/changelogs/3.1.0.md
Merge pull request #2009 from sminnee/uploadfield-choose-new-file

NEW 'Choose another file' button on upload field AAS-917
Avoid collision of status flags in tree items when updating tree nodes

Fixes silverstripe/silverstripe-cms#445
See https://github.com/silverstripe/silverstripe-framework/pull/1996
Thanks to Jean-Fabien for getting this started
Merge pull request #2014 from chillu/pulls/445-tree-statusflags

Avoid collision of status flags in tree items when updating tree nodes
Add explicit extension trigger to preview iframe updates.
Merge pull request #2016 from mateusz/preview-trigger

Add explicit extension trigger to preview iframe updates.