[cmake-developers] optional-install topic

[Brad King]

Nils,

The topic adds the variable "CMAKE_DISABLE_INSTALL_RULES".
For skipping certain generation features we already have the
convention "CMAKE_SKIP_..." for variable names.  Perhaps
"CMAKE_SKIP_INSTALL_RULES"?

Please add a RunCMake.install test with a case covering the warning:

+    mf->IssueMessage(cmake::WARNING,
+      "CMAKE_DISABLE_INSTALL_RULES was enabled even though "
+      "installation rules have been specified");

Also please look at adding a full test that verifies that
no cmake_install.cmake file is generated and if possible that
"cmake --build . --target install" fails.

Thanks,
-Brad