Rewrite the datashape grammar document with a new grammar
Rewrite the datashape grammar document with a new grammar

cowlicks/datashape,blaze/datashape,llllllllll/datashape,cowlicks/datashape,ContinuumIO/datashape,cpcloud/datashape,quantopian/datashape,quantopian/datashape,llllllllll/datashape,FrancescAlted/datashape,aterrel/datashape,cpcloud/datashape,blaze/datashape,aterrel/datashape,ContinuumIO/datashape,FrancescAlted/datashape