CMakePM: Enable ANSI codes colored output

Qt Creator is able to display colored output for the _Compile Output_
and _General Messages_ panes.

This commit enables CMake and tools to use this functionality.

See https://cmake.org/cmake/help/latest/variable/
CMAKE_COLOR_DIAGNOSTICS.html and http://bixense.com/clicolors/ for more
details.

Change-Id: Ied4058bbd2522750d559b05d585092830ce3a911
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/cmakeprojectmanager/builddirparameters.cpp

@@ -66,6 +66,8 @@ BuildDirParameters::BuildDirParameters(CMakeBuildSystem *buildSystem)
         environment.set("ICECC", "no");
 
     environment.set("QTC_RUN", "1");
+    environment.setFallback("CMAKE_COLOR_DIAGNOSTICS", "1");
+    environment.setFallback("CLICOLOR_FORCE", "1");
 
     cmakeToolId = CMakeKitAspect::cmakeToolId(k);
 }

src/plugins/cmakeprojectmanager/cmakebuildstep.cpp

@@ -261,6 +261,8 @@ CMakeBuildStep::CMakeBuildStep(BuildStepList *bsl, Id id) :
             env.set("NINJA_STATUS", ninjaProgressString + "%o/sec] ");
         env.modify(m_userEnvironmentChanges);
 
+        env.setFallback("CLICOLOR_FORCE", "1");
+
         if (useStaging())
             env.set("DESTDIR", stagingDir().path());
     });