DockerFile update for improvement (#1568)
DockerFile update for improvement (#1568)

Docker file changes for image size improvements.
zuohuadong/laradock,schiggi/laradock,springjk/laradock,springjk/laradock,bestlong/laradock,luciano-jr/laradock,bestlong/laradock,zuohuadong/laradock,hnquang112/laradock,jinnawat/laradock,hnquang112/laradock,cjnchk/laradock,schiggi/laradock,bestlong/laradock,arkadiusjonczek/laradock,cjnchk/laradock,jinnawat/laradock,ralphowino/laradock,springjk/laradock,cjnchk/laradock,AliveCorpse/laradock,Harmonic/laradock,cjnchk/laradock,arkadiusjonczek/laradock,arkadiusjonczek/laradock,ralphowino/laradock,arkadiusjonczek/laradock,Harmonic/laradock,jinnawat/laradock,Harmonic/laradock,ralphowino/laradock,Harmonic/laradock,ralphowino/laradock,bestlong/laradock,bestlong/laradock,schiggi/laradock,hnquang112/laradock,zuohuadong/laradock,jinnawat/laradock,LaraDock/laradock,hnquang112/laradock,schiggi/laradock,zuohuadong/laradock,AliveCorpse/laradock,springjk/laradock,luciano-jr/laradock