Split out z/OS package data

In issue #49 a case was made that we have several sources for open
source software being developed for IBM z/OS and it now makes sense to
split up the repositories for easier maintenance and improved accuracy.

This commit splits out the following:

- Rocket Software into ZOS_Rocket_Software.json

- Everything from github.com/IBM/IBM-Z-zOS/ into IBM_Z_zOS.json

- Everything maintained by the Open Mainframe Project into ZOS_OMP.json

Once this split is completed, we will work on updates to these files.

ZOS_Software_List.json remains as a generic place to put any software
that doesn't neatly fit into another category, but I have removed all
tools related to the z/OS Open Tools project, since it's very outdated
and there's another effort in progress to complete adding these tools
into their own source file (see:
openmainframeproject/software-discovery-tool#124).

Signed-off-by: Elizabeth K. Joseph <[email protected]>

Author: pleia2