Extended-tap-oracle

* Log value of mine_sql [30](https://github.com/singer-io/tap-oracle/pull/30)

* Set a maximum length on Singer Decimals, where a decimal past the cap is normalized via `decimal.normalize()` [28](https://github.com/singer-io/tap-oracle/pull/28)

* Values with Decimal precision will now be written as strings with a custom `singer.decimal` format in order to maintain that precision through the pipeline [26](https://github.com/singer-io/tap-oracle/pull/26)

* Increase default numeric scale from `6` to `38` [24](https://github.com/singer-io/tap-oracle/pull/24)

* Backwards incompatible change to the way that data types are discovered and parsed [22](https://github.com/singer-io/tap-oracle/pull/22)
* Oracle numeric types with a null scale (`NUMBER` and `NUMBER(*)`) will now be correctly discovered as floating point types rather than integers.
* This may cause downstream issues with loading and reporting, so a major bump is required.

* Adds handling for columns that do not have a datatype -- those columns will have `inclusion`=`unavailable` and `sql-datatype`=`"None"` [19](https://github.com/singer-io/tap-oracle/pull/19)