Refactored ComicImage classes: added virtual requestRedraw(size, matrix) method
that calls createRedrawJob().
jobCompleted method calls new redraw() method.
Added "natural" sorting of files (Chapter99, Chapter100, Chapter101
rather than Chapter100, Chapter101, Chapter99).
Merge pull request #3 from veddan/master

Natural sorting of files
Merge branch 'master' into refactor

Conflicts:
	src/DirReader.cpp