Refactor: Move login out of models (#16199)

`models` does far too much. In particular it handles all `UserSignin`.

It shouldn't be responsible for calling LDAP, SMTP or PAM for signing in.

Therefore we should move this code out of `models`.

This code has to depend on `models` - therefore it belongs in `services`.

There is a package in `services` called `auth` and clearly this functionality belongs in there.

Plan:

- [x] Change `auth.Auth` to `auth.Method` - as they represent methods of authentication.
- [x] Move `models.UserSignIn` into `auth`
- [x] Move `models.ExternalUserLogin`
- [x] Move most of the `LoginVia*` methods to `auth` or subpackages
- [x] Move Resynchronize functionality to `auth`
  - Involved some restructuring of `models/ssh_key.go` to reduce the size of this massive file and simplify its files.
- [x] Move the rest of the LDAP functionality in to the ldap subpackage
- [x] Re-factor the login sources to express an interfaces `auth.Source`?
  - I've done this through some smaller interfaces Authenticator and Synchronizable - which would allow us to extend things in future
- [x] Now LDAP is out of models - need to think about modules/auth/ldap and I think all of that functionality might just be moveable
- [x] Similarly a lot Oauth2 functionality need not be in models too and should be moved to services/auth/source/oauth2
  - [x] modules/auth/oauth2/oauth2.go uses xorm... This is naughty - probably need to move this into models.
  - [x] models/oauth2.go - mostly should be in modules/auth/oauth2 or services/auth/source/oauth2 
- [x] More simplifications of login_source.go may need to be done
- Allow wiring in of notify registration -  *this can now easily be done - but I think we should do it in another PR*  - see #16178 
- More refactors...?
  - OpenID should probably become an auth Method but I think that can be left for another PR
  - Methods should also probably be cleaned up  - again another PR I think.
  - SSPI still needs more refactors.* Rename auth.Auth auth.Method
* Restructure ssh_key.go

- move functions from models/user.go that relate to ssh_key to ssh_key
- split ssh_key.go to try create clearer function domains for allow for
future refactors here.

Signed-off-by: Andrew Thornton <art27@cantab.net>

templates/admin/auth/edit.tmpl

@@ -22,7 +22,7 @@
 
 				<!-- LDAP and DLDAP -->
 				{{if or .Source.IsLDAP .Source.IsDLDAP}}
-					{{ $cfg:=.Source.LDAP }}
+					{{ $cfg:=.Source.Cfg }}
 					<div class="inline required field {{if .Err_SecurityProtocol}}error{{end}}">
 						<label>{{.i18n.Tr "admin.auths.security_protocol"}}</label>
 						<div class="ui selection security-protocol dropdown">
@@ -151,7 +151,7 @@
 
 				<!-- SMTP -->
 				{{if .Source.IsSMTP}}
-					{{ $cfg:=.Source.SMTP }}
+					{{ $cfg:=.Source.Cfg }}
 					<div class="inline required field">
 						<label>{{.i18n.Tr "admin.auths.smtp_auth"}}</label>
 						<div class="ui selection type dropdown">
@@ -182,7 +182,7 @@
 
 				<!-- PAM -->
 				{{if .Source.IsPAM}}
-					{{ $cfg:=.Source.PAM }}
+					{{ $cfg:=.Source.Cfg }}
 					<div class="required field">
 						<label for="pam_service_name">{{.i18n.Tr "admin.auths.pam_service_name"}}</label>
 						<input id="pam_service_name" name="pam_service_name" value="{{$cfg.ServiceName}}" required>
@@ -195,7 +195,7 @@
 
 				<!-- OAuth2 -->
 				{{if .Source.IsOAuth2}}
-					{{ $cfg:=.Source.OAuth2 }}
+					{{ $cfg:=.Source.Cfg }}
 					<div class="inline required field">
 						<label>{{.i18n.Tr "admin.auths.oauth2_provider"}}</label>
 						<div class="ui selection type dropdown">
@@ -258,7 +258,7 @@
 
 				<!-- SSPI -->
 				{{if .Source.IsSSPI}}
-					{{ $cfg:=.Source.SSPI }}
+					{{ $cfg:=.Source.Cfg }}
 					<div class="field">
 						<div class="ui checkbox">
 							<label for="sspi_auto_create_users"><strong>{{.i18n.Tr "admin.auths.sspi_auto_create_users"}}</strong></label>
@@ -325,7 +325,7 @@
 				<div class="inline field">
 					<div class="ui checkbox">
 						<label><strong>{{.i18n.Tr "admin.auths.activated"}}</strong></label>
-						<input name="is_active" type="checkbox" {{if .Source.IsActived}}checked{{end}}>
+						<input name="is_active" type="checkbox" {{if .Source.IsActive}}checked{{end}}>
 					</div>
 				</div>
 

templates/admin/auth/list.tmpl

@@ -28,7 +28,7 @@
 							<td>{{.ID}}</td>
 							<td><a href="{{AppSubUrl}}/admin/auths/{{.ID}}">{{.Name}}</a></td>
 							<td>{{.TypeName}}</td>
-							<td>{{if .IsActived}}{{svg "octicon-check"}}{{else}}{{svg "octicon-x"}}{{end}}</td>
+							<td>{{if .IsActive}}{{svg "octicon-check"}}{{else}}{{svg "octicon-x"}}{{end}}</td>
 							<td><span class="poping up" data-content="{{.UpdatedUnix.FormatShort}}" data-variation="tiny">{{.UpdatedUnix.FormatShort}}</span></td>
 							<td><span class="poping up" data-content="{{.CreatedUnix.FormatLong}}" data-variation="tiny">{{.CreatedUnix.FormatShort}}</span></td>
 							<td><a href="{{AppSubUrl}}/admin/auths/{{.ID}}">{{svg "octicon-pencil"}}</a></td>