Modified PTS user guide to include INV channel LEDs testing: 10 blinking LEDs instead of 6--ADDED unstaged files

- replaced lengthy text that probably no one was going to read for nice
pictures describing how to install the RTM board testers
- added these pictures to the repo
- updated one link in the References section

This is needed for user-based PTS. Without write permission to
(in particular) the log folder, a PTS system ran from its specific user
cannot gain access to the scripts stored and copied under the pts user,
which is what the current PTS setup looks like.

The correction is related to the description in the CSR.RTM bit field, therefore
it only concerns the documentation, not the generated code.

The changes are more documentation-related, bit field descriptions have been
corrected and made clearer.

Hence the README link change