add set_heroku_vars_changed and run_heroku_config_if_settings_changed to roboconf.sh
check key and value together; more informative output; add comment
use [[ ... && ... ]]
uncommenting line that actually configures Heroku vars (that I commented out during testing)
add comments describing functions
rename set_heroku_vars_changed to detect_heroku_vars_changed
expand explanation of detect_heroku_vars_changed
Merge pull request #1 from JamesLavin/add_heroku_config_functions

add set_heroku_vars_changed and run_heroku_config_if_settings_changed to...