Fixing double slashes in capabilities when gwc is deploy on root context '/'
Added initializer for the ImageIO SPIs
Merge pull request #271 from n-lagomarsini/issue270

[Issue:270] Wrong handling of the ImageIO and ImageIO-Ext plugins
Merge pull request #267 from smithkm/transient-expire

Add expiry time to TransientCache, Fixes #264 and #265
Merge pull request #268 from torse/rootctx

Fixing double slashes in capabilities href urls when gwc is deploy on root context...