Adds GoogleAnalytics external submodule. Refs #47.
Registers tracking ID with google analytics sdk. Refs #47.
Moves EHTab_vc to correct subdirectory. Refs #47.
Adds EHGai_vc for screen tracking. Refs #47.
Implements EHGai_tvc for tables. Refs #47.
Tracks other apps opened. Refs #47.
Adds tracking of importation/exportation. Refs #47.
Documents task in changes log. Refs #47.
Mentions Google Analytics license. Refs #47.
Updates release steps, changes dev version to 4.1. Refs #47.
Merge branch 'feature/t47_google_analytics'