This catches unavoidable conditional insert deadlocks in lazy_create and retries them

Bug: 1014875
Change-Id: I210797f4add7908a0b3e3312bc6dffbd7d687825
hide superfluous navbar items in narrow viewports

This keeps the navbar at a single line down to widths of about 850px.
Below that it will wrap sensibly to two lines.

Bug: 670438
Change-Id: I2dc8a1b5d59ac5628caed6c502f2643eea907d45
Merge branch 'release-0.15' into develop