Update Ant Dependency to 1.9.3
documentation and typos
Merge pull request #368 from kaendfinger/update-ant-dependency

Update Ant Dependency to 1.9.3
upgrade xstream and xmlunit dependencies
doco tweaks
GDK restyling: lowercasing tag names
GDK restyling: copy resources (in particular the groovy icon and the stylesheet)
GDK restyling: more tag lowercasing
GDK restyling: use the center class for all bodies
GDK restyling: changes to the left frame pages, and update of the main content by removing some unneeded nav sections without pages
GDK restyling: adapt the navigation bar
GDK restyling: styling of the classes template
Merge pull request #370 from glaforge/gdk-restyled

GDK documentation restyling
GROOVY-6627: Fixed regression in generics type checking