Update VE core submodule to master (384618f)

New changes:
a6393a9 Localisation updates from https://translatewiki.net.
e9fbb24 Followup 96ff968: use this.$element after it's initialized, not before
22ee9d4 Follow-up: If717ef98 – Re-add subscript and superscript removes to DM nodes

Change-Id: If01a4ded55bc1a14f632bfc27dbf7a92029f1b41