Add short Cassaforte recipe
Add information about distributed counters
Add information about limit
Add license agreement
Add an introduction section, elaborate on what cassandra is and what it's good for
Moving introduction to discussion
Fixup fn arguments recipe headers
Add install cassandra section
Merge pull request #143 from ifesdjeen/cassaforte

Add short Cassaforte recipe
Merge branch 'master' of https://github.com/clojure-cookbook/clojure-cookbook
Include cassandra recipe in databases chapter. /cc @ifesdjeen