Initialization of dependent repositories:
-----------------------------------------
This only needs to be once when the repository is defined.  This notes
is maintained for reference when copying to a new repository, or just
in general information on how to add dependent repositories. 

For repositories belonging to the same group (efabless) as the design, use:

	 git submodule add ../panamax.git dependencies/panamax

For repositories with a different ownership, use, e.g.,:

	git submodule add ../../RTimothyEdwards/sky130_ef_ip__analog_switches \
		dependencies/sky130_ef_ip__analog_switches

Submodules should be updated recursively, since some dependencies have
their own dependencies.  This creates redundant versions of some circuits,
but will keep the version that was checked in with the top level repository.
Tools like "magic" will check the repository commit hash and treat cells
with the same name from different directories that are from the same
commit of the same repository as the same cell.  If cells have the same
name but exist in different commits of the same repository or different
repositories, then magic will throw an error.

Be sure to do

	git submodule update --init --recursive

if the top level repository was not cloned with the --recursive option.