The last known usage of custom measure feature is the ability to use it to define which projects should be used in a portfolio.
As it will be possible to use tags to define projects used in a portfolio (see https://jira.sonarsource.com/browse/MMF-939), we can safely deprecate the custom metric/measure feature.
- Deprecate all web services from api/custom_measures
- Deprecate api/views/manual_measure
- Deprecate api/views/mode