fix #815 use redcarpet (markdown) instead of redcloth (textile)
replace RedCloth with redcarpet
replace RedCloth with redcarpet
Merge branch 'refs/heads/master' into ticker_redcarpet

* refs/heads/master:
  try removing the ruby gems restriction
add back postgres to gem lock file
Merge pull request #818 from concerto/ticker_redcarpet

use redcarpet (markdown) instead of redcloth (textile)