Updated README.md
Updated README.md

Updated the README.md with a more detailed Quickstart instructions
to create an Echo demo. Updated the project name accordingly.

mattWillis/crosswalk-ios,ericzhou2008/crosswalk-ios,minggangw/crosswalk-ios,hgl888/crosswalk-ios,mattWillis/crosswalk-ios,jondong/crosswalk-ios,negherbon/crosswalk-ios,jondong/crosswalk-ios,negherbon/crosswalk-ios,mattWillis/crosswalk-ios,crosswalk-project/crosswalk-ios,crosswalk-project/crosswalk-ios,ericzhou2008/crosswalk-ios,ericzhou2008/crosswalk-ios,hgl888/crosswalk-ios,ericzhou2008/crosswalk-ios,hgl888/crosswalk-ios,RafuCater/crosswalk-ios,crosswalk-project/crosswalk-ios,jondong/crosswalk-ios,RafuCater/crosswalk-ios,jondong/crosswalk-ios,mattWillis/crosswalk-ios,crosswalk-project/crosswalk-ios,negherbon/crosswalk-ios,hgl888/crosswalk-ios,minggangw/crosswalk-ios,minggangw/crosswalk-ios,RafuCater/crosswalk-ios,negherbon/crosswalk-ios,minggangw/crosswalk-ios,RafuCater/crosswalk-ios