Add generic dejagnu support for running benchmarks.

Adds a generic framework for running the benchmarks.  Have updated
the existing run.exp script (just run the benchmarks) to use the new
framework, and have added perf-stat.exp (uses the kernel perf counters
to measure instructions) and have rewritten measure.exp as
mageec-wand.exp to use the new framework.

ChangeLog:

	* beebs.test/measure.exp: Deleted.
	* beebs.test/mageec-wand.exp: New file.
	* beebs.test/perf-stat.exp: New file.
	* lib/beebs.exp: New file.
	* beebs.test/run.exp: Update to use beebs.exp support.
Use global env in mageec-wand.exp.

Need to access the global value of env in order to see the environment
variables.

ChangeLog:

	* beebs.test/mageec-wand.exp (beebs_cleanup_after_all_benchmarks):
	Pull in global env.
	(beebs_setup_before_benchmark_run): Likewise.
Restore the beebs_run_benchmark procedure.

The beebs_run_benchmark procedure was not being set to call
default_beebs_run_benchmark as it should.

ChangeLog

	* lib/beebs.exp (beebs_restore_default_procs): Restore
	beebs_run_benchmark too.
Merge remote-tracking branch 'tjteru/master' into dejagnu3
Update new dejagnu to handle newly split benchmarks.

Benchmarks are now split, so one binary per directory.  This commit
updates the dejagnu work to reflect this.

ChangeLog:

	* beebs.test/mageec-wand.exp (beebs_setup_before_benchmark_run):
	Rename to ...
	(beebs_setup_before_benchmark): ... this.
	(beebs_cleanup_after_benchmark_run): Rename to ...
	(beebs_cleanup_after_benchmark): ... this.
	(beebs_cleanup_after_benchmark_run): Update, use benchmark not
	filename to identify results.
	* beebs.test/perf-stat.exp (beebs_run_benchmark): Update
	parameters.  The filename is now a full path, use as such.  Use
	benchmark, not directory to identify results.
	* lib/beebs.exp (default_beebs_filter_benchmarks): Renamed to...
	(default_beebs_filter_benchmark): ...this. Rename parameters.
	(default_beebs_setup_before_benchmark): Add filename parameter.
	(default_beebs_cleanup_after_benchmark): Add filename parameter.
	(default_beebs_setup_before_benchmark_run): Deleted.
	(default_beebs_cleanup_after_benchmark_run): Deleted.
	(beebs_get_benchmark_files): Deleted.
	(default_beebs_announce): Remove directory parameter.
	(default_beebs_run_benchmark): Likewise.
	(beebs_run_all_benchmarks): Remove calls to deleted functions.
	Assume only one binary in each benchmark directory.  Update
	parameters on remaining calls.
	(beebs_restore_default_procs): Reorder procedures.  Update
	parameters.
Merge pull request #18 from T-J-Teru/dejagnu3

Merge in changes to support running the benchmarks using dejagnu.