Migrate to JavSE 7

##### Update JRE/JDK to Java 7

This should eliminate Eclipse warnings for developers who don't have a version 5 and 6 JRE or JDK on their systems (but hopefully have version 7 JDK.)

##### Infer type parameters of constructors

This should silence potential warnings and make the code more robust in the face of future changes.

##### Use try-resource management

This should drastically simplify resource management code, eliminate warnings, and ensure resources aren't being leaked.

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This closes #193.