CMake: Remove magic configuration from CMake

Get rid of magic configuration handling in the CMakeProjectManager.

* Use CMakeCache.txt as the sole source of truth, do not keep
  a shadow copy of configuration in the .user file
* Have initial CMake arguments that are easy to edit in batch
  (Fixes: QTCREATORBUG-18179) used whenever no CMakeCache.txt
  file is in the build directory. These allow for any thing that
  can be passed to CMake on the command line.
  (Fixes: QTCREATORBUG-16296)
* Ask when changes to CMake configuration were not applied
  (Fixes: QTCREATORBUG-18504)
* Run cmake with arguments effecting its configuration only when
  the CMake settings are changed in the UI, run CMake without any
  special arguments in all other cases.
* Get rid of the confusing dialog used to keep settings in sync between
  what is in CMakeCache.txt and Creator (Fixes: QTCREATORBUG-23218)

Change-Id: I26d55be7df733f084f5691ecf7d7b4352f58b8e7
Reviewed-by: Cristian Adam <cristian.adam@qt.io>

src/plugins/cmakeprojectmanager/builddirparameters.h

@@ -54,21 +54,13 @@ public:
     Utils::FilePath sourceDirectory;
     Utils::FilePath buildDirectory;
     Utils::FilePath workDirectory; // either buildDirectory or a QTemporaryDirectory!
+
     Utils::Environment environment;
+
     Core::Id cmakeToolId;
 
-    QByteArray cxxToolChainId;
-    QByteArray cToolChainId;
-
-    Utils::MacroExpander *expander = nullptr;
-
-    CMakeConfig configuration;
-
-    QString generator;
-    QString extraGenerator;
-    QString platform;
-    QString toolset;
-    QStringList generatorArguments;
+    QStringList initialCMakeArguments;
+    QStringList extraCMakeArguments;
 };
 
 } // namespace Internal