v0.13.0: base compatibility for Elephant protocol upgrade

[evias]

Milestone: Elephant

• Added SignSchema to make KeyPair generation compatible with either of Catapult and NIS.
• Added SignSchema with KECCAK_REVERSED_KEY and SHA3. The SDK by default uses SHA3 which is the Catapult signature schema.
• Fixed transaction versions back to version 1
• Added signTransactionGivenSignatures to cope with off chain aggregated complete transaction co signing.

[coveralls]

Pull Request Test Coverage Report for Build 564

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.06%) to 60.721%

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Totals
Change from base Build 562:	-0.06%
Covered Lines:	5871
Relevant Lines:	8355

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💛 - Coveralls