Updated makefile

 * Makefile now uses a variable for rebar.
 * Makefile now has a xref task.
Rebar config updates.

 * Lager is now included as dependecy since it's used in the console.erl
 * Lager parser transformer is used.
Made all components xref-clean.
Merge pull request #5 from Licenser/makefile-updates

Updated makefile
Merge pull request #4 from Licenser/rebar-config-updates

Rebar config updates.
Merge pull request #3 from Licenser/xreffed

Made all components xref-clean.
Merge remote-tracking branch 'origin/master' into riak_core_2_wip

Conflicts:
	riak_core.rebar.config
	riak_core_wm_ping.erl