debug_utilities: Create the ast_coredumper utility

This utility allows easy manipulation of asterisk coredumps.

* Configurable search paths and patterns for existing coredumps
* Can generate a consistent coredump from the running instance
* Can dump the lock_infos table from a coredump
* Dumps backtraces to separate files...
  - thread apply 1 bt full -> <coredump>.thread1.txt
  - thread apply all bt -> <coredump>.brief.txt
  - thread apply all bt full -> <coredump>.full.txt
  - lock_infos table -> <coredump>.locks.txt
* Can tarball corefiles and optionally delete them after processing
* Can tarball results files and optionally delete them after processing
* Converts ':' in coredump and results file names '-' to facilitate
  uploading.  Jira for instance, won't accept file names with colons
  in them.

Tested on Fedora24+, Ubuntu14+, Debian6+, CentOS6+ and FreeBSD9+[1].

[1] For *BSDs, the "devel/gdb" package might have to be installed to
get a recent gdb.  The utility will check all instances of gdb
it finds in $PATH and if one isn't found that can run python, it
prints a friendly error.

Change-Id: I935d37ab9db85ef923f32b05579897f0893d33cd
(cherry picked from commit cb47b45560)

configs/samples/ast_debug_tools.conf.sample

@@ -0,0 +1,40 @@
+#
+# This file is used by the Asterisk debug tools.
+# Unlike other Asterisk config files, this one is
+# "sourced" by bash and must adhere to bash semantics.
+#
+
+# A list of coredumps and/or coredump search patterns.
+# Bash extended globs are enabled and any resulting files
+# that aren't actually coredumps are silently ignored
+# so you can be liberal with the globs.
+#
+# If your patterns contains spaces be sure to only quote
+# the portion of the pattern that DOESN'T contain wildcard
+# expressions.  If you quote the whole pattern, it won't
+# be expanded and the glob characters will be treated as
+# literals.
+#
+# The exclusion of files ending ".txt" is just for
+# demonstration purposes as non-coredumps will be ignored
+# anyway.
+COREDUMPS=(/tmp/core[-._]asterisk!(*.txt) /tmp/core[-._]$(hostname)!(*.txt))
+
+# Date command for the "running" coredump and tarballs.
+# DATEFORMAT will be executed to get the timestamp.
+# Don't put quotes around the format string or they'll be
+# treated as literal characters.  Also be aware of colons
+# in the output as you can't upload files with colons in
+# the name to Jira.
+#
+# Unix timestamp
+#DATEFORMAT='date +%s.%N'
+#
+# Unix timestamp on *BSD/MacOS after installing coreutils
+#DATEFORMAT='gdate +%s.%N'
+#
+# Readable GMT
+#DATEFORMAT='date -u +%FT%H-%M-%S%z'
+#
+# Readable Local time
+DATEFORMAT='date +%FT%H-%M-%S%z'