almost complete telegram user verification

When signing up, the user is given a pin code which they send to a
telegram bot. This provides user verification, but more importantly
allows the bot to message the user, as the Telegram API requires the
user to interact with the bot before it can do the opposite.

The bot should recognize the correct language, but a /lang command is
also provided to change it.

The verification process is pretty much functional but ui is still
broken, and it isn't properly integrated yet.

lang/form/en-us.json

@@ -17,11 +17,14 @@
         "successContinueButton": "Continue",
         "confirmationRequired": "Email confirmation required",
         "confirmationRequiredMessage": "Please check your email inbox to verify your address.",
-        "yourAccountIsValidUntil": "Your account will be valid until {date}."
+        "yourAccountIsValidUntil": "Your account will be valid until {date}.",
+        "linkTelegram": "Link Telegram",
+        "sendPIN": "Send the PIN below to the bot, then come back here to link your account."
     },
     "notifications": {
         "errorUserExists": "User already exists.",
-        "errorInvalidCode": "Invalid invite code."
+        "errorInvalidCode": "Invalid invite code.",
+        "telegramVerified": "Telegram account verified."
     },
     "validationStrings": {
         "length": {