SVN_SILENT made messages (.desktop file)
Support for default include path and definitions on CLang compiler.

When I compile Kdevelop using only in my Debian Testing Clang 3.4, the defaults include paths is not recognized. In the code I will see that the functions are only for GCC and MSVC, with this patch now with Clang are recognized both, the include paths, and standard definitions.

REVIEW: 117938
BUG: 314218
FIXED-IN: 4.7
Fixup missing clang compiler support in Qt4.

Clang does support initializer lists just fine. This fixes the
compilation of KDevelop with clang after commit 520869abe77fe7fa.
Kill the MissingIncludeCompletionModel and worker.

Most of its functionality was already copied in the CompletionContext.
Just removing it showed nearly no regressions in my tests. The stuff
that is required, I now added to other places to make it work.

Also, for the fun of it: Note how not only was the functionality
partially duplicated by the MissingIncludeModel and normal completion
context, no! The doSpecialProcessing method in the model was also
usually called twice, once via updateCompletionRange and once from
startWithExpression...

Additionally, I don't see the need for a special worker thread here
in the first place. Only if normal code completion fails do we want
the missing include completion items, no?

Since this code is not unit tested at all, please test this! I hope
I did not miss any magic functionality of the model...
Hack around the race condition in CppUtils::findIncludePaths.

This time, we ensure the DUChain is not locked while delegating
work to the foreground thread via the infamous ForegroundLock.

It seems to work. But I said that the last time as well, so please
test! Generally, this code is a mess and I'm desparately awaiting
the time where I can say: "Good riddance!" kdev-clang to the rescue!