fix(grunt): make grunt server listen to 0.0.0.0

it was set to localhost only which doesn't work within docker image
wip(docker)
fix(docker)
Merge branch 'fix-connect' of github.com:petrjasek/superdesk-client into add-docker
readme: added info about docker
repo: added vagrant and according readme lines
Merge remote-tracking branch 'petr/fix-connect' into devel
Merge remote-tracking branch 'yauhen/add-vagrant' into devel