added executeJSONArray
updated README to document JSONArrays
Merge pull request #72 from nickaknudson/issue_56

Proposed fix for Issue 56
Merge branch 'master' of https://github.com/koush/AndroidAsync

# By Nick Knudson
# Via Koushik Dutta (1) and Nick Knudson (1)
* 'master' of https://github.com/koush/AndroidAsync:
  updated README to document JSONArrays
  added executeJSONArray