account: Add the ability to create an account without any password

Modify the accountcreationwizard and the accountimportexportview to
enable account with no password set.

Change-Id: Id2304f363d0eea8f19d607dedb71f80dea005d8f
diff --git a/src/accountmigrationview.cpp b/src/accountmigrationview.cpp
index 1cf09a9..fb09f52 100644
--- a/src/accountmigrationview.cpp
+++ b/src/accountmigrationview.cpp
@@ -174,14 +174,7 @@
 
     const gchar *password = gtk_entry_get_text(GTK_ENTRY(priv->entry_password));
 
-    if (strlen(password) > 0)
-    {
-        gtk_widget_set_sensitive(priv->button_migrate_account, TRUE);
-    }
-    else
-    {
-        gtk_widget_set_sensitive(priv->button_migrate_account, FALSE);
-    }
+    gtk_widget_set_sensitive(priv->button_migrate_account, TRUE);
 }
 
 static void