Fix for https://github.com/jayfajardo/openlibrary/issues/16

Refactored request to DRY up some methods
added new Details class to consumer the Details API using the ?jscmd=details parameter
updated readme for the details class
Merge branch 'dresselm-master'

* dresselm-master:
  Fix for https://github.com/jayfajardo/openlibrary/issues/16
added Matt Dressel as contributor
Merge branch 'details' of https://github.com/okcscott/openlibrary into okcscott-details

* 'details' of https://github.com/okcscott/openlibrary:
  updated readme for the details class
  added new Details class to consumer the Details API using the ?jscmd=details parameter
Merge branch 'okcscott-details'

* okcscott-details:
  updated readme for the details class
  added new Details class to consumer the Details API using the ?jscmd=details parameter
added Scott Lesser as contributor