fixed upper case Seq inconsistency
added base class feature handling and updated fasta lazy class to have all required methods
added base class level support for feature parsing
updated tests to work with new features property
older typo in docstring
feature bin collection changed getter behavior, added init argument for control, and added relevant tests
Abstract lazy base: init now uses feature bin collection
modified fasta behavior returning features
added pep8 compliant class docstrings to _lazy
added GenBank indexing and lazy loading basic support and tests