Reordered code to prevent stack overflows

By changing the method slightly, the stack only fill up at half
the speed from the previous implementation. This should hopefully
prevent most overflows on complex documents.
try/catch for unparseable colours
Merge branch 'master' into css_support

Conflicts:
	src/main/java/net/nightwhistler/htmlspanner/HtmlSpanner.java
	src/main/java/net/nightwhistler/htmlspanner/handlers/FontHandler.java