Update VisualEditor submodule to latest master

* 16831b1 - mw.ViewPageTarget: Add support for spam blacklist (2 hours ago) <Timo Tijhof>
* bc7836d - mw.ViewPageTarget: Swap captcha and badtoken logic in onSaveError (10 hours ago) <Timo Tijhof>
* 56ef8cb - Create MWResizeableNode mixin to control defaultSize flag (2 hours ago) <Ed Sanders>
* fd0f4ff - Run UnicodeJS tests from Special:JavaScriptTest/qunit (68 minutes ago) <Timo Tijhof>
* b40cd4d - Remove 'visualeditor-feedback-link' from RL module (2 hours ago) <Timo Tijhof>
* 70d1503 - Localisation updates from http://translatewiki.net. (4 hours ago) <Translation updater bot>
* bdbae42 - Fake superscript style for references generated as spans (7 hours ago) <Ed Sanders>

Change-Id: I12f52719ecafd7488bb0041916aabb46989a72bf