Bug fix: make links go to matching 'play' Drupal sites for each test or srri site.
e.g. dg-srri.kcptech.com goes to play-srri.kcptech.com, dg-test.kcptech.com goes to play-test.kcptech.com.
Affects File>Manage Documents; Gear menu>Help, Report a problem, Release Notes, About; Login>Register, Recover Password.
app_controller.js [create URLs using new method getDrupalSubdomain, move strings to strings.js]
authorization.js [create URLs using new method getDrupalSubdomain, move strings to strings.js]
core.js [new method getDrualSubdomain() gets variant URLS]
main_page.js [fix last check in, to make local var names more standard]
strings.js [URL and window title strings extracted from above files]