Rad

-------------------

- Add ``IPAC/SSC`` to ``origin`` enum. [160]

- Add archive information to ``ref_file`` and fix indentation there. [161]

-------------------

- Removed CRDS version information from basic schema. [146]

- Changed the dimensionality of the err variable in ramp. [149]

- Create docs for RTD. [151]

- Moved gw_function_start_time, gw_function_end_time, and
gw_acq_exec_stat from GuideStar to GuideWindow. Removed duplicate
gw time entries. [154]

- Changed optical filter name W146 to F146. [156]

- Moved archive related information in the ``basic`` schema directly
into a tagged object for easier retrieval by ASDF. [153, 158, 159]

- Fix ref_file schema. [157]

-------------------

- Remove start_time and end_time from the observation schema [142]

-------------------

- exposure schema update in include descriptions [139]

- Moved ma_table_name and ma_table_number from observation to exposure schemas. [138]

-------------------

- Initial Guide Window Schema [120]

- Enumerate aperture_name in the aperture schema [129]

- Remove exptype and p_keywords from Distortion Model [127]

- Added photom keyword attribute to cal_step schema. [132]

- Added ma_table_number to observation and dark schemas. [134]

- Create distortion schema [122]

-------------------

- Moved detector list to new file for importing to both data and reference schemas. [119]

- Added support for Distortion reference files. Tweaked schema for WFI detector list. [122]

- Changed input_unit and output_unit keyword types, titles, and tests. [126]

- Removed exptype and p_keywords from Distortion schema. [128]