[WIP] Add Google Book covers to search results and record view

Closes #112 and relates to #78 

Pending: Fix formatting issue in search results 

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![searchworks-issue78-2](https://cloud.githubusercontent.com/assets/302258/3043536/906bc336-e107-11e3-9184-e6a1cb8156e2.png)
![searchworks-issue78-1](https://cloud.githubusercontent.com/assets/302258/3043537/906c9478-e107-11e3-884e-7dd7228d08d8.png)