KDE(Libs)4Support rename

[Alex Merry]

I have a local commit renaming kde4support to kdelibs4support.  It's
long and tedious and repetitive, so I don't see much point in putting it
on RB, but the gist is:

kde4support -> kdelibs4support
KDE4SUPPORT -> KDELIBS4SUPPORT
KDE4Support -> KDELibs4Support
KDE4 Support -> KDELibs 4 Support (eg: top of README.md)
Kde4support -> KdeLibs4Support (function names in autotests)

This goes for file names as well as contents.  The result is that both
find -iname \*kde4support\*
and
git grep -i kde4support
come up empty.

Are there any objections to me pushing this (along with relevant changes
- mostly to CMake code and comments - in other repos, of course)?

Alex