[Launcher UI] add ability to select geometry from a predefined list

[jamesscottbrown]

@senakafdo suggested that there should be pre-defined list of layout types, so that rather than haivng to enter the dimensions and positions of the new section in pixels, a user can first select a layout from a list (e.g., 5 equal sections) and then a position in that layout (e.g., the leftmost section).

[oserban]

This could work as an expansion of the "full screen" feature we are currently offering. The options could be to first select the application template (i.e. full screen, 5 equal sections, 4 equal sections, half of the observatory) and then the location where this could be deployed (2nd section in a 4 section partition).