Removed plot fill keyword in make_gaussian_image example
Updating getting started example
Merge pull request #114 from bsipocz/docs_extending_mainpage_example

Extending mainpage example
Move overlap functions in geometry package
Adding __init__.py for geometry subpackage
Change aperture.py to use geometry sub-package
Removing duplicate functions
Place for geometry docs
Adding more docs to circular_overlap_grid
Adding more docs to elliptical_overlap_grid
Adding __all__
adding calling sequence
Changing link