catch NoMethodError in clear_caching for dalli>2.0

dalli now raises NoMethodError on delete_matched
fixes #2130
Use new relative link support
Merge pull request #2166 from sbeam/master

fix for #2130, NoMethodError with dalli >2.0
Specify 2.0.0 not 2.0 for CI
Updated image URLs in guides.
Updated link to contributing doc.
Conflicts:
	doc/guides/2 - Refinery Basics/7 - Translate Refinery.textile
Fixes #1628 by updating Dragonfly API usage.
Added failure scenario for uploading an image of incorrect format

* Also added scenarios for uploading an image of in insert mode (used in wysiwyg editor)

Fixes #2168
Refine JS to not hold a variable.
Update license year
Merge pull request #2183 from jtallant/patch-1

Update license year

[ci skip]
update license year in readme
Avoid redundancy leading to annual commits.
Fix 1.9 hash syntax being present.

Introduced in ed6964f1
Added contribution guidelines. (ht: @bcardarella)
Add Turkish translation (for some of the engines).
Require Rails 3.1.11 or 3.2.12 for security.
Translated images and resources to Turkish
Clean up the YAML a little.
Do not convert user input to symbols