ENH: Use library wrapper in the "EXECUTABLE_ONLY" case

This will allow custom wrapper to execute some code before the main
entry point in both the [exec + shared lib] and [exec only] cases.

The macro "MODULE_STATIC" has also been introduced and can be tested
within the wrapper to discriminate both cases.

Change the component associated with Archive target from RuntimeLibraries
to Development. That way, static library won't be packaged.

See Slicer issue #3008 - http://na-mic.org/Bug/view.php?id=3008
Merge branch 'use-wrapper-for-exec-only-case'

* use-wrapper-for-exec-only-case:
  ENH: Use library wrapper in the "EXECUTABLE_ONLY" case
COMP: SlicerExecutionModelConfig: Set default variable only if not defined

It is now possible for a project to globally override the default value
of output directories and library cxx wrapper.
Merge branch 'config-set-default-vars-only-if-needed'

* config-set-default-vars-only-if-needed:
  COMP: SlicerExecutionModelConfig: Set default variable only if not defined
Add option allowing to specify which link flags to use with CLI executable

The SlicerExecutionModle can be configured with option SlicerExecutionModel_DEFAULT_CLI_EXECUTABLE_LINK_FLAGS
or the set of flags to use can locally be overridden setting variable
SlicerExecutionModel_CLI_EXECUTABLE_LINK_FLAGS.
Merge branch 'macosx-link-executable-with-rpath' into pu

* macosx-link-executable-with-rpath:
  Add option allowing to specify which link flags to use with CLI executable