Functions which don't have grouping information is grouped as Actions - pull request to Sitrus

As the result of changes in this pull request, the following categories are updated to include Actions grouping information

`Core.Scripting`
`Core.Evaluate`
`Core.List.Evaluate`
`Core.Input`
`Core.Logic.Conditional`
`Core.Strings`
`Core.View`
`Builtin Functions`
`Operators`

Added Unit Test for `ProcessNodeCategory()`.

This pull request is connected with this pull request https://github.com/DynamoDS/Dynamo/pull/2016.