Documentation of Application Configuration Options

[Sebastian Huber]

Hello,

I reworked the documentation of the application configuration options in 
the last weeks. All 149 options are now documented. Several options are 
obsolete in RTEMS 5.1.

The documentation is generated via a script from these specification items:

https://git.rtems.org/sebh/rtems-qual.git/tree/spec/acfg/opt/

Please review the documentation, there were changes throughout all options.

https://docs.rtems.org/branches/master/c-user/config/index.html