GCS Config: rename Module_Settings_Widget to ModuleSettingsWidget

This is consistent with all the other UI naming conventions in our
code.
GCS Config: stubs for module config page
GCS Config: add module tab
GCS Config: show module settings
Module settings: remove from the hardware settings tab
Modules tab: add the module settings into a tab box

This allows easily adding the other widgets within that tab
box such as TxPid, Autotune, and CameraStab.
Merge pull request #766 from peabody124/modules_tab

Give the modules settings its own tab