Add more steps to README_pushing_to_maven.md
Add more steps to README_pushing_to_maven.md

luinnx/TourGuide,horie1024/TourGuide,MichiganLabs/TourGuide,nousmotards/TourGuide,shyamkumarm/TourGuide,worker8/TourGuide,wenion/TourGuide,0359xiaodong/TourGuide,Shedings/TourGuide,huynhchanhuy/TourGuide,cnevinc/TourGuide,YutaKase6/TourGuide,worker8/TourGuide,sylsi/TourGuide,finally-vince/TourGuide,AndroidWx/TourGuide,luwei2012/TourGuide,weikipeng/TourGuide,tommytcchan/TourGuide,wsygwg/TourGuide,changjiashuai/TourGuide,MaTriXy/TourGuide,ckurtm/TourGuide