Update OOjs UI to v0.1.0-pre (51f922ba17)

New changes:
57f95fe Add OO.ui.InlineMenuWidget
2ebcd42 Localisation updates from https://translatewiki.net.
1ba6137 Make fieldsets and stack panels more compact
064484f Only pay attention to left mouse button events in PopupToolGroup
584ed14 Convert styles to LESS and implement grunt task
ad906c5 Add documentation for -1 tabIndex option, which disables tab indexing
3f962db Manage active state of BookletLayout pages
5f3ee83 Disable vertical scrolling in continuous layout mode
96ae071 Make text inputs gray when disabled
51f922b Refactor OutlineControlsWidget, add remove button

Change-Id: If83857915732c2d4615b653ce9e9d0fe9c20744b