Fix minor typo in README
Updated the variant creation methods to be type safe.

By building directly from the API methods when available.
Also updated null arguments to Option.
Merge pull request #6 from elmer-garduno/serialize_java_api_objects

Serialize java api objects
Consolidated transforming from the Java API objects to the serializable version on a ReadBuilder object.

This adds type safety as the values are no longer transformed into a Map, the class constructor is invoked directly using the appropriate types.
Merge pull request #7 from elmer-garduno/serialize_java_api_objects

Updated ReadsIterator to the ReadBuilding pattern.
Merge branch 'master' into spark_pca_example
Merge branch 'master' into spark_pca_example
Added PCA first cut