Updates fabfile to run 'npm install' on lint check
Updates fabfile to run 'npm install' on lint check

If grunt is not installed, js linting fails to execute and the whole
'fab ... check' process returns an error code. This update makes sure
grunt is installed.

recklessromeo/otm-core,RickMohr/otm-core,recklessromeo/otm-core,maurizi/otm-core,RickMohr/otm-core,RickMohr/otm-core,clever-crow-consulting/otm-core,clever-crow-consulting/otm-core,maurizi/otm-core,maurizi/otm-core,recklessromeo/otm-core,clever-crow-consulting/otm-core,RickMohr/otm-core,maurizi/otm-core,recklessromeo/otm-core,clever-crow-consulting/otm-core