Merge remote-tracking branch 'upstream/master'

Conflicts:
	README.md
remove pycharm internal files
remove pycharm internal files
reorganized files on the repository, clening up
reorganized files on the repository, clening up
reorganized files on the repository, clening up
reorganized files on the repository, clening up
reorganized files on the repository, clening up
reorganized files on the repository, clening up
reorganized files on the repository, clening up
replace executed notebook with metadata saved in jsonld format (still to be completed)
added anonymous username to be used when no username is provided.
added check for "ecoop_username" environment var (used by runipy)
added new methods to add metadata at notebook level, add prov for NIN, changed aoutput prov-key to :  ecoop_prov
Merge pull request #10 from epifanio/master

master