Add / before temp file name

Related: http://lists.wikimedia.org/pipermail/labs-l/2014-July/002722.html
Merge pull request #76 from stwalkerster/patch-1

Add / character before temp file name
Various tidying to Image class
 * Mostly doc fixes
 * Also implement $force for image upload history
Update internal uses of imageinfo() in line with new return format.

Technically a breaking change, but was already broken due to filtering
of data returned by the list handler.

In addition, title is no longer accepted as a param, but rather
canonicaltitle.
Strip out $this->local, not (no longer?) returned by imageinfo
Wrap assert checks in isset() to prevent warnings
Code style update
Merge pull request #80 from Jarry1250/assert

Wrap assert checks in isset() to prevent warnings
Merge pull request #79 from Jarry1250/image2

Restore image class back to functionality
Emergency fix (one fatal, one warning)

Resolve inability to edit by moving if/else back inside loop when it hard
got pushed outside of that loop.

Also, resolve one warning about array member being defined.
Merge pull request #82 from Jarry1250/emergencyfix

Emergency fix (one fatal, one warning)
Merge pull request #84 from MW-Peachy/master

Release update for stable