Pyblueprints

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- Updated requirements file

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- Transactions refactored delegating management to the restclient

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- Added Transactional operations support
- Added dropIndex functionality for Neo4j-API
- Added code examples to documentation
- Added tests

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- Bugfixes

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- Fixed removeProperty bug

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- Added unittests
- Added getEdge, removeProperty and getBothEdges methods
- Returning None in NotFoundErrors instead of raising exception
- Bugfixes