WIP: switch from ui to newui

This CL proposes 3 changes:

1) When making the embeds, any .html files in newui is rewwritten
on the fly so that the resulting embed uses all.js instead of
individual .js files.

2) Various bugs and paths in the newui/*.js files were fixed so that
everything works when using all.js

3) pkg/server/ui.go was minimally changed so that all ui requests
now use newui, hence the old ui is not used anymore.
In a next step, we can move back everything from newui/ into ui/ and
completely get rid of the dichotomy in ui.go

Nothing is done yet to roll-sum all.js into chunks.

Change-Id: I381d8ddf3a2bbe37e3c4b1c4bf423f16beffaaf4
wat

Change-Id: I88e943106457d20551b5945089fbaa32e402f342