Multiplication needs to be 64bit, to handle overflow regardless of the bittedness of the machine, fixes #771#
Windows compatibility
Don't install mp_compile if multiprocessing.Pool() fails, or if 1 process is going to be used
Updated CHANGES.rst
Bump the versions
Merge pull request #792 from wiredfool/2.5.x

Release 2.5.1
Bump [ci skip]
Skip Known Bad Tests
Known Bad tests -- skipping jpeg2k tests on travis on OSX
Icns DOS fix --  CVE-2014-3589

Found and reported by Andrew Drake of dropbox.com
Bump Versions/Changelog
J2k DOS fix --  CVE-2014-3598

Found and reported by Andrew Drake of dropbox.com
Bump Version/Changelog
Merge 2.5.x branch to master, get 2.5.3 in CHANGES.rst