set eslints max-len to 120

[zaggino]

while 80 might be too narrow in some cases, anything over 120 means you have to scroll horizontally when reviewing pull requests on GH which is a real pain

cc @ficristo @petetnt

[petetnt]

I am totally okay with this. Long lines are hard to follow, on GH editor as they are in Brackets.

Might be fixable with eslint --fix too if there's tons of lines spanning over 120 characters too.

[ficristo]

I'm okay too.