Made the change but not finished.  Refs #6526.
Added filter label, and "No filter" to dropdown. Refs #8199.
Added one more output property.  Refs #6526.
Changed output property name.  Refs #6526.

The original name contained 'Workspace'.  simpleapi.py treats any output
property containing 'Workspace' as workspace.
Execute catalog algorithms asynchronously. Refs #8321.

- Added a helper method to execute asynchronously to prevent duplication of code.
Make loading asynchronous. Refs #8321.
Set instrument in search to user default instrument. Refs #8204.

- Removed sorting as instruments are ordered by name in the query.
Refs #8163. Add run_number to log list.

Don't add it automatically. Gets represented as double for now.
Refs #8345 Flipped list of indicies used to plot.
Added algorithm helper class. Refs #8322.

- This class reduces the code across algorithms.
Refactored `CatalogSearch`. Refs #8322.

- Removed unused attributes from `CatalogSearchParam`.
- Updated `ICat3Helper.cpp` to work correctly with new interface (e.g. when "my data" is checked).
- Updated documentation for algorithm.
Fix version numbering in Python sphinx documentation.

Refs #8363
Refs #8352. Removing an unnecessary boolean.
Tidied `CatalogSearchParam` class. Refs #8322.

- Removed unnecessary comments in header. Made them more concise and consistent with other header files in Mantid.
- Removed RB number search as it is no longer used in the interface.
- Added investigator surname search back to `CatalogSearch`.
Tidied up `CatalogMyDataSearch`. Refs #8322.

- Removed unused headers and added call to helper class.
Refactored catalog logout algorithm. Refs #8322.

- Removed unimplemented method `doLogout()`.
Tidied Catalog login algorithm. Refs #8322.

- Removed unnecessary catalog error method.
Updated CatalogListInstruments. Refs #8322.
Made use of algorithm helper class. Refs #8322.

- Removed unused methods (`filterLogFiles` & `isDataFile`) and related properties.
Use algorithm helper class. Refs #8322.

- Updated documentation for each algorithm and tidied header files.