add function asTriple
change use asTriple for updateSource-data
change option saveEndpoint to updateEndpoint
add gitignore
add reset updateSource before submit widgets for a certain resource
add extend bootstrap3 stylesheets (submenus)
add literalLanguageTags and literalDatatypes functions
add run widgets init method
add submenus for datatype and language, add indicators for set datatype or language
add set updateEndpoint