build: Update grunt-jscs and fix violations new in JSCS 1.9.0

JSCS implemented about a dozen new rules, some of which have
been added to the "wikimedia" preset per our coding conventions.

https://github.com/jscs-dev/node-jscs/pull/843

Change-Id: I60cc93aee392017a50af5594c076e93de8d515dc
build: Bump grunt-contrib-less from 0.12.0 to 1.0.0

No-op change in CSS output.

Change-Id: Iad115f464bd37a4a00ac250255a5ec5ebe039364
build: Bump karma dependency from 0.12.25 to 0.12.28

Change-Id: Ib967cc7681c06031d3ae399c30ddd6655ce6fceb
Merge "build: Update grunt-jscs and fix violations new in JSCS 1.9.0"
Merge "build: Bump grunt-contrib-less from 0.12.0 to 1.0.0"
Merge "build: Bump karma dependency from 0.12.25 to 0.12.28"