[RFAv2 0/3] Implement 'set print frame-info|frame-arguments

[Philippe Waroquiers <philippe.waroquiers@skynet.be>]

When printing big stacktraces having a lot of functions with a lot of
arguments, it can be handy to see a lot less information in the
printed frames.

With the new settings, it is possible to have backtraces such as:
  (gdb) bt
  #0  break_me ()
  #1  call_me (...)
  #2  main ()
  (gdb)

that are only showing the level, the function name and the presence of
arguments.

Compared to V1, the changes are:
* Handled the comment of Andreas Schwab : do not abbreviate words
  in 'set print fram-info' values, and use dash instead of underscore.
* Handled the comment of Tom about updating py-framefilter.c
  + updated py-framefilter.exp to test the new setting with python
  frame filter.
* Handled the comments of Eli about the documentation and NEWS.