Add argument app name for command buildassets

hshassets/management/commands/buildassets.py

hshassets/management/commands/initassets.py

hshassets/static/hshassets/img/favicon.ico

hshassets/static/hshassets/js/bulma-accordion.js

hshassets/static/hshassets/js/bulma-navbar-burger.js

hshassets/static/hshassets/js/common.js

hshassets/static/hshassets/js/jquery-3.2.1.js

hshassets/static/hshassets/js/session_timer.js

hshassets/static/hshassets/styles.css

hshassets/static/hshassets/styles.min.css

hshassets/templates/hshassets/includes/nav_lang_flags.html

hshassets/utils.py