change Failure to Panic in docstring
impl Error, FromError for SqliteError, with static description and optional dynamic detail
  - bump rev from 0.0.1 to 0.1.1 to reflect a bit of maturity
  - give description() in high level API errors:
    - "unexpected SQLITE_ROW from update"
    - "no such row name/number"
  - just panic!() if decode_result() gets a bad result arg
  - just .unwrap() strptime/strftime; SQLITE_TIME_FMT is unit-tested
  - rename SqliteError enumeration to SqliteErrorCode
  - no need for (SqliteError, String) idiom; just use with_detail
    - unit test for with_detail()
    - no need to use SqliteError in several cases
      - format use statements for cleaner diffs
  - factor error_result() out of decode_result()