add upstart scripts installation to build_from_source
add service start up to master and slave recipe in source installation type and cleanup rspecs and serverspecs.
rename master_or_slave to role, remove duplicated test and fix some spacing, which @mthssdrbrg comemnted.
paved top README and example READMEs
Merge pull request #12 from everpeace/feature/upstart_scripts_for_source_installation

Add upstart script to build_from_source and service start up to master and slave.
Update README.md

add 'and start mesos-[master|slave]' to [master|slave] recipe.