Add open file dialog and print help message actions

Closes #315
Merge remote-tracking branch 'finetjul/315-ctkconsole-open-file'

* finetjul/315-ctkconsole-open-file:
  Add open file dialog and print help message actions

Conflicts:
	Libs/Widgets/Testing/Cpp/CMakeLists.txt
	Libs/Widgets/ctkConsole.cpp