add 0.7 to travis nodejs version
add 0.7 to travis nodejs version

parthiban019/jsforce,pcon/jsforce,jesperkristensen/jsforce,saleswise/jsforce,polidog/jsforce,jsforce/jsforce,saleswise/jsforce,parthiban019/jsforce,pcon/jsforce,stomita/node-salesforce,bhaskarmelkani/jsforce,rdietrick/jsforce,saleswise/jsforce,nutthawan/jsforce,jesperkristensen/jsforce,jsforce/jsforce,jdcrensh/jsforce,jsforce/jsforce,lkatney/jsforce,bhaskarmelkani/jsforce,joeferraro/jsforce,joeferraro/jsforce,lkatney/jsforce,nutthawan/jsforce,kimchouard/jsforce,jdcrensh/jsforce,pcon/jsforce