CppTools: Move QtVersion and BuildTargetType

QtVersion to utils/cpplanguage_details.h which already contains similar
flags.

BuildTargetType to ProjectExplorer, next to BuildTargetInfo (but not in the
same header to not pull that in everywhere).

Removes dependency on ProjectPart from RawProjectPart.

Change-Id: I5791065e4266f20c2657ee4b1b594df04b238a1c
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/cmakeprojectmanager/servermodereader.cpp

@@ -335,8 +335,8 @@ CppTools::RawProjectParts ServerModeReader::createRawProjectParts(QString &error
         rpp.setFiles(transform(fg->sources, &FilePath::toString));
 
         const bool isExecutable = fg->target->type == "EXECUTABLE";
-        rpp.setBuildTargetType(isExecutable ? CppTools::ProjectPart::Executable
-                                            : CppTools::ProjectPart::Library);
+        rpp.setBuildTargetType(isExecutable ? ProjectExplorer::BuildTargetType::Executable
+                                            : ProjectExplorer::BuildTargetType::Library);
         rpps.append(rpp);
     }