updating node version in travis to the one we use on the ROV as there is a problem installing grunt-cli on travis
updating node version in travis to the one we use on the ROV as there is a problem installing grunt-cli on travis

kavi87/openrov-cockpit,kavi87/openrov-cockpit,OpenROV/openrov-cockpit,kavi87/openrov-cockpit,chaudhryjunaid/openrov-cockpit,BenjaminTsai/openrov-cockpit,johan--/openrov-cockpit,OpenROV/openrov-cockpit,BrianAdams/openrov-cockpit,BrianAdams/openrov-cockpit,BrianAdams/openrov-cockpit,BenjaminTsai/openrov-cockpit,johan--/openrov-cockpit,spiderkeys/openrov-cockpit,BrianAdams/openrov-cockpit,chaudhryjunaid/openrov-cockpit,OpenROV/openrov-cockpit,spiderkeys/openrov-cockpit,kavi87/openrov-cockpit,spiderkeys/openrov-cockpit,johan--/openrov-cockpit,BenjaminTsai/openrov-cockpit,BenjaminTsai/openrov-cockpit,chaudhryjunaid/openrov-cockpit,johan--/openrov-cockpit,BrianAdams/openrov-cockpit,chaudhryjunaid/openrov-cockpit,BenjaminTsai/openrov-cockpit,johan--/openrov-cockpit,spiderkeys/openrov-cockpit,kavi87/openrov-cockpit,chaudhryjunaid/openrov-cockpit,spiderkeys/openrov-cockpit