[binutils-gdb] Allow breakpoint commands to be set from Python

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT a913fffbdee21fdd50e8de0596358be425775678 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: a913fffbdee21fdd50e8de0596358be425775678

Allow breakpoint commands to be set from Python

This changes the Python API so that breakpoint commands can be set by
writing to the "commands" attribute.

ChangeLog
2018-05-04  Tom Tromey  <tom@tromey.com>

	PR python/22731:
	* NEWS: Mention that breakpoint commands are writable.
	* python/py-breakpoint.c (bppy_set_commands): New function.
	(breakpoint_object_getset) <"commands">: Use it.

doc/ChangeLog
2018-05-04  Tom Tromey  <tom@tromey.com>

	PR python/22731:
	* python.texi (Breakpoints In Python): Mention that "commands" is
	writable.

testsuite/ChangeLog
2018-05-04  Tom Tromey  <tom@tromey.com>

	PR python/22731:
	* gdb.python/py-breakpoint.exp: Test setting breakpoint commands.