* [NOD-849] Cover ffldb/transaction with tests.
* [NOD-849] Cover cursor.go with tests.
* [NOD-849] Cover ldb/transaction with tests.
* [NOD-849] Cover location.go with tests.
* [NOD-849] Write TestFlatFileMultiFileRollback.
* [NOD-849] Fix merge errors.
* [NOD-849] Fix a comment.
* [NOD-849] Fix a comment.
* [NOD-849] Add a test that makes sure that files get deleted on rollback.
* [NOD-849] Add a test that makes sure that serializeLocation serialized to an expected value.
* [NOD-849] Improve TestFlatFileLocationDeserializationErrors.
* [NOD-849] Fix a copy+paste error.
* [NOD-849] Explain maxFileSize = 16.
* [NOD-849] Remove redundant RollbackUnlessClosed call.
* [NOD-849] Extract bucket to a variable in TestCursorSanity.
* [NOD-849] Rename TestKeyValueTransactionCommit to TestTransactionCommitForLevelDBMethods.
* [NOD-849] Extract prepareXXX into separate functions.
* [NOD-849] Simplify function calls in TestTransactionCloseErrors.
* [NOD-849] Extract validateCurrentCursorKeyAndValue to a separate function.
* [NOD-849] Add a comment over TestCursorSanity.
* [NOD-849] Add a comment over function in TestCursorCloseErrors.
* [NOD-849] Add a comment over function in TestTransactionCloseErrors.
* [NOD-849] Separate TestTransactionCloseErrors to TestTransactionCommitErrors and TestTransactionRollbackErrors.
* [NOD-849] Separate TestTransactionCloseErrors to TestTransactionCommitErrors and TestTransactionRollbackErrors.
* [NOD-849] Fix copy+paste error in comments.
* [NOD-849] Fix merge errors.
* [NOD-849] Merge TestTransactionCommitErrors and TestTransactionRollbackErrors into TestTransactionCloseErrors.
* [NOD-849] Move prepareDatabaseForTest into ffldb_test.go.
* [NOD-849] Add cursorKey to Value error messages in validateCurrentCursorKeyAndValue.
