add toggable option for achievement system.
clearer language in config.yml
Merge branch 'master' into issue104

Conflicts:
	build.number
	src/plugin.yml
Merge branch 'development' into issue104
clean up unused import
better throw message.
Merge branch 'development' into issue104
Refactor to move YamlConfig file code into its own method.
basic avatar achievement loader implemented. Finishes #116.