doc/wrs-user-manual: improvements/fixes

- clearn up section on tools
  * added rvlan-debug/status
  * names of some were commented out, uncommented
  * updated/expanded some descriptions
  * added reference to later chapters with more details
- updated/extended section on items added in v6.1

Signed-off-by: Adam Wujek <dev_public@wujek.eu>