Merge pull request #297 from eile/master

Fix OS X build and cppcheck
Added two new window attributes to set the width and height.
Externally the attributes can only be set with the global config options/
environmental variables EQ_WINDOW_IATTR_HINT_WIDTH and
EQ_WINDOW_IATTR_HINT_HEIGHT. Each overrides the default window width/height
when no configuration file is provided.
Merge cleanups