Add travis build status to README.md
Add travis build status to README.md

sprylab/emojicon,fashioncj/emojicon,hgl888/emojicon,martinbiix/emoji,fanxu123/emojicon,lankong/emojicon,gdky005/emojicon,common2015/emojicon,zhangyuwan0/emojicon,shiguang1120/emojicon,siwangqishiq/emojicon,murat8505/icon_library_show_TextView_WhatsApp-emojicon,chaitanya0bhagvan/emojicon,kontalk/emojicon,Data5tream/emoji-lib,jehad-suliman/emojicon,ivan-jukic/emojicon,qq287597590/EmojViewForAndroid,angcyo/emojicon,zmsoft/emojicon,binaryfork/emojicon,martinbiix/emoji,TonySCruze/emojicon,SyllaJay/emojicon,Sshah88/emojicon,chuangWu/emojicon,brooksgod/emojicon,bestwpw/emojicon,fhchina/emojicon,rockerhieu/emojicon,android-gems/emojicon,SatanEd/emojicon,tanweijiu/emojicon