[PATCH 0/3] Target remote mode fork and exec support

[Don Breazeal <donb@codesourcery.com>]

This patchset implements support fork and exec events for target
remote mode Linux targets.  This is done primarily by enabling
functionality that had previously been restricted to extended-remote
mode, and by preventing gdbserver from exiting until there are no
more active inferiors left.

There are a number of tests that had to be modified to enable them in
target-remote mode.

The GDB manual sections on connecting to a remote target were modified
and reorganized to clarify the distinction between remote,
extended-remote, and multiprocess, and to collect related information
into subsections.

The patches include:

PATCH 1/3: Implements target remote mode fork and exec event support.
PATCH 2/3: Enables fork and exec tests for target remote mode.
PATCH 3/3: Updates documentation for fork and exec events with target
           remote.

Tested on x86_64 Linux with native, remote, and extended-remote.  Also
tried it with Pedro's patch that modified gdbserver exit criteria,
https://sourceware.org/ml/gdb-patches/2015-10/msg00222.html, and saw no
regressions.

Thanks, Don