morebits: Use csrfToken in mw.user.tokens

We need to migrate our token usage properly (#615, noted in #616) but one simple step is moving from `mw.user.tokens.get('editToken')` to `mw.user.tokens.get('csrfToken')`.  Using `csrfToken` in favor of `editToken` was done back in 2015/2016 with the move away from `action=tokens` to `meta=tokens`.  Both `editToken` and `csrfToken` have been provided in the `mw.user.tokens` object for quite some time, and the former is finally being deprecated (see [T233442](https://phabricator.wikimedia.org/T233442)).  The presence of the `edittoken` attribute in xml responses is unchanged.

morebits.js

@@ -1793,7 +1793,7 @@ Morebits.wiki.page = function(pageName, currentAction) {
 			action: 'edit',
 			title: ctx.pageName,
 			summary: ctx.editSummary,
-			token: canUseMwUserToken ? mw.user.tokens.get('editToken') : ctx.editToken,
+			token: canUseMwUserToken ? mw.user.tokens.get('csrfToken') : ctx.editToken,
 			watchlist: ctx.watchlistOption
 		};
 
@@ -2477,7 +2477,7 @@ Morebits.wiki.page = function(pageName, currentAction) {
 			}
 		}
 
-		return !!mw.user.tokens.get('editToken');
+		return !!mw.user.tokens.get('csrfToken');
 	};
 
 	// callback from loadSuccess() for append() and prepend() threads
@@ -2775,7 +2775,7 @@ Morebits.wiki.page = function(pageName, currentAction) {
 		var pageTitle, token;
 
 		if (fnCanUseMwUserToken('delete')) {
-			token = mw.user.tokens.get('editToken');
+			token = mw.user.tokens.get('csrfToken');
 			pageTitle = ctx.pageName;
 		} else {
 			var xml = ctx.deleteApi.getXML();
@@ -2864,7 +2864,7 @@ Morebits.wiki.page = function(pageName, currentAction) {
 		// but until then (#615) the stupid hack below should work for
 		// undeletion.
 		if (fnCanUseMwUserToken('undelete')) {
-			token = mw.user.tokens.get('editToken');
+			token = mw.user.tokens.get('csrfToken');
 			pageTitle = ctx.pageName;
 		} else {
 			var xml = ctx.undeleteApi.getXML();
@@ -2887,7 +2887,7 @@ Morebits.wiki.page = function(pageName, currentAction) {
 			}
 
 			// KLUDGE:
-			token = mw.user.tokens.get('editToken');
+			token = mw.user.tokens.get('csrfToken');
 			pageTitle = ctx.pageName;
 		}