Clang: Locator: Add filters for classes, includes, functions

Filters are based on symbol query where they are
not implemented yet.

Change-Id: Id826beaf6bb47a81363c36780d7254a85a9a3cc9
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/clangrefactoring/clangrefactoring.qbs

@@ -59,6 +59,7 @@ QtcPlugin {
         "function.h",
         "functionsfilter.cpp",
         "functionsfilter.h",
+        "include.h",
         "includesfilter.cpp",
         "includesfilter.h",
         "locatorfilter.cpp",