Sparkle release notes for 0.93

git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk@3407 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834
Update sparkle appcast for 0.93

git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk@3408 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834
- updated link to repo in readme
- image loader will report last SDL error if loading failed
- fixed parsing of floats from H3 txt's

git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk@3409 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834
- fixed "get txt" console command
- command "extract" to extract file by name
- command "def2bmp" to convert def into set of frames.

git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk@3410 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834