PLT-4332 Position field for Users (#4632)

* Add User.Position field to store & model.

* GOFMT

* Add Position to user settings.

* Unit tests.

* Add position to profile popup.

* i18n

* Fix log message for invalid position.

* Add Position field attribute to LDAP config.

* Add Position field attribute to SAML config.

* Reword empty position message.

* Change Position Max Length to 35.

* Better invalid position error message.

* Add new fields to config.json.

* Ensure position is never longer than max when displayed.

* Hard limit of 64 chars with soft limit still 35

* Put field with other attributes.

config/config.json

@@ -186,6 +186,7 @@
         "UsernameAttribute": "",
         "NicknameAttribute": "",
         "IdAttribute": "",
+        "PositionAttribute": "",
         "SyncIntervalMinutes": 60,
         "SkipCertificateVerification": false,
         "QueryTimeout": 60,
@@ -218,6 +219,7 @@
         "UsernameAttribute": "",
         "NicknameAttribute": "",
         "LocaleAttribute": "",
+        "PositionAttribute": "",
         "LoginButtonText": "With SAML"
     },
     "NativeAppSettings": {