Sandbox 14246 cosmo integration files

See merge request !391

Sandbox#16008 test sigb connexion factorisation

See merge request !375

Dev #14218 add custom fields to articles

See merge request !390

Conflicts:
	VERSIONS

Merge remote-tracking branch 'refs/remotes/afi/dev_#15526_google_var_to_generic_var' into afi-master

Conflicts:
	cosmogramme/php/_init.php

Dev#14605 library field in purchase suggestion form

See merge request !387

Dev #15264 upgrade contact form

See merge request !381

fix regressions in translation form

+ Mail subject [Bokeh] instead of [AFI-OPAC]
+ Checkbox in options screen now behave normally
+ Typo in label of library selector fixed
+ Ensure that when no library have mail, selector is not displayed