Create basic package manager

[rawiriblundell]

Create a basic package manager to grab libraries from online resources and install them into the libpath.

For more advanced bash package management, there's the likes of awesome, basher, bpkg, shundle and others. Investigate the paths used by those projects and add them to the potential paths that are parsed when automatically building the libpath. This way, a user can, for example, install a library package using basher, and after the next init, those libraries will be available.

One of these existing package managers might be a good match to simply fork for the purposes of this FR.