BUG Upload: File versioning with existing files
reinsert oldFilePath = relativeFilePath in while loop
Merge branch 'pr/3570' into 3.1
fixed RemoteURL css for issue 1086
Merge pull request #3572 from LukePercy/Issue#1086

fixed RemoteURL css for CMS issue 1086
Update DropdownField.php
Merge pull request #3573 from MichaelCSLWeb/patch-2

Update DropdownField.php
Update cache-control.md

Added useful information after half an hour trying to have cache working :)
FIX: Prevent JSON response showing when re-opening closed tab (fixes silverstripe/silverstripe-cms#1121)
fixed and tested object has_extension
Merge pull request #3575 from kinglozzer/pulls/fix-reopen-tab-response

FIX: Prevent JSON response showing when re-opening closed tab (fixes silverstripe/silverstripe-cms#1121)
Merge pull request #3484 from dnadesign/object_has_extension_fix

fixed and tested object has_extension
Session keys are case sensitive
Merge pull request #3578 from g4b0/patch-4

Session keys are case sensitive