add work-in-progress manual spreadsheet creation instructions to new project docs
Remove Mercurial from system requirements, we don't need it now that pip version of google-api-python-client incorporates a bugfix.
repeat caveat
reformat automatic creation section to indicate it is wonky
Update docs to reflect proper Google auth workflow.
Merge branch 'fix_newproject' of https://github.com/newsapps/tarbell-template into fix_newproject