Add intial content for system management templates

include/class.i18n.php

include/client/login.inc.php

include/i18n/en_US/templates/page/access-link.yaml

include/i18n/en_US/templates/page/banner-client.yaml

include/i18n/en_US/templates/page/banner-staff.yaml

include/i18n/en_US/templates/page/pwreset-client.yaml

include/i18n/en_US/templates/page/pwreset-staff.yaml

include/i18n/en_US/templates/page/registration-client.yaml

include/i18n/en_US/templates/page/registration-staff.yaml

include/staff/login.tpl.php

include/staff/settings-access.inc.php

include/staff/templates/content-manage.tmpl.php

scp/login.php