This commit changes Open() to provide an additional Options argument. The options
argument currently only has a Timeout which will cause the Open() to return
ErrTimeout if a file lock cannot be obtained in time.
Fixes#207.
This commit removes several memory allocations occurring on every page and also caches the freelist map used when iterating over the pages. This results in significantly better performance.
This commit changes Tx.Check() to return a channel through which check errors are returned. This allows
errors to be found before checking the entire data file.
This commit removes the DB.Check() function and instead makes the user decide
whether a transaction should be writable or read-only. Tx.Check() is not safe
to use concurrently on a read-only transaction, however, it significantly
improves the performance of it.
Ben Johnson