Amalgamate v0.1.14

• Test exclusive iteration. Closes #62.
• Unit test reverse iteration. See #62.
• Remove dead conditional. See #62.
• Unit test searching by key. See #62.
• Unit test creation errors. See #62.
• Unit test rollback. See #62.
• Mark conflicts. See #62. Closes #100.
• Upgrade b-tree to 2.0.0-alpha.34.
• Create a forced amalgamate to run at startup. See #62.
• Reopen, implement version lookup. See #62.
• Remove sundry serialization options. See #62.

Closes #101.