Add functions to jump to specific modules.

Usage:
...aosp/$ gomod libbase
...aosp/system/core/base$

Using in alias:
alias g=gomod
complete -F _complete-android-module-names g

...aosp/$ g libbase
...aosp/system/core/base$

Nothing in Android keeps an up to date index of all Android modules
and their locations between builds. However, there is a target
'module-info.json' which is used to contain some of that information.
This module can be updated using the command 'refreshmod' added
here, but it will also be updated during a normal Android build.

This also adds auto-complete for m.

Bug: N/A
Test: manual
Change-Id: I06b0b87c308b9fe2798dbc29225906cc30fe59fe