Support registration & login with phone number (#742)

* WIP msisdn sign in

* A mostly working country picker

* Fix bug where you'dbe logged out after registering

Stop the guest sync, otherwise it gets 401ed for using a guest
access token for a non-guest, causing us to beliebe we've been
logged out.

* Use InteractiveAuth component for registration

* Fix tests

* Remove old signup code

* Signup -> Login

Now that Signup contains no code whatsoever related to signing up,
rename it to Login. Get rid of the Signup class.

* Stray newline

* Fix more merge failing

* Get phone country & number to the right place

* More-or-less working msisdn auth component

* Send the bind_msisdn param on registration

* Refinements to country dropdown

Rendering the whole lot when the component was rendered just makes
the page load really slow, so just show 2 at a time and rely on
type-to-search.

Make type-to-search always display an exact iso2 match first

* Propagate initial inputs to the phone input

* Support msisdn login

* semicolon

* Fix PropTypes

* Oops, use the 1qst element of the array

Not the array of object keys which has no particular order

* Make dropdown/countrydropdown controlled

* Unused line

* Add note on DOM layout

* onOptionChange is required

* More docs

* Add missing propTypes

* Don't resume promise on error

* Use React.Children to manipulate children

* Make catch less weird

* Fix null dereference

Assuming [0] of an empty list == undefined doesn't work if you're
then taking a property of it.

src/Login.js

@@ -105,21 +105,38 @@ export default class Login {
         });
     }
 
-    loginViaPassword(username, pass) {
-        var self = this;
-        var isEmail = username.indexOf("@") > 0;
-        var loginParams = {
-            password: pass,
-            initial_device_display_name: this._defaultDeviceDisplayName,
-        };
-        if (isEmail) {
-            loginParams.medium = 'email';
-            loginParams.address = username;
+    loginViaPassword(username, phoneCountry, phoneNumber, pass) {
+        const self = this;
+
+        const isEmail = username.indexOf("@") > 0;
+
+        let identifier;
+        if (phoneCountry && phoneNumber) {
+            identifier = {
+                type: 'm.id.phone',
+                country: phoneCountry,
+                number: phoneNumber,
+            };
+        } else if (isEmail) {
+            identifier = {
+                type: 'm.id.thirdparty',
+                medium: 'email',
+                address: username,
+            };
         } else {
-            loginParams.user = username;
+            identifier = {
+                type: 'm.id.user',
+                user: username,
+            };
         }
 
-        var client = this._createTemporaryClient();
+        const loginParams = {
+            password: pass,
+            identifier: identifier,
+            initial_device_display_name: this._defaultDeviceDisplayName,
+        };
+
+        const client = this._createTemporaryClient();
         return client.login('m.login.password', loginParams).then(function(data) {
             return q({
                 homeserverUrl: self._hsUrl,