logic: indexer commands

* replaced parser arguments by project specific IndexerCommands that know everything the indexer needs to know to do its job
* added different language and project specific indexers that know how to handle a certain kind of indexer command
* refactored FileManager and FileRegister to have less overhead
* removed no-rtti restriction for clang files in lib cxx
* uncommented deprecated interprocess code.

fortune cookie message = Happiness will bring you good luck.

src/test/helper/TestFileRegister.cpp

@@ -0,0 +1,20 @@
+#include "TestFileRegister.h"
+
+TestFileRegister::TestFileRegister()
+	: FileRegister(FileRegisterStateData(), std::set<FilePath>(), std::set<FilePath>())
+{
+}
+
+TestFileRegister::~TestFileRegister()
+{
+}
+
+bool TestFileRegister::fileIsIndexed(const FilePath& filePath) const
+{
+	return false;
+}
+
+bool TestFileRegister::hasFilePath(const FilePath& filePath) const
+{
+	return true;
+}