Macro Input tool enhancement

[Linas]

Changing the Macro Input tool in an existing macro is dangerous and can result in unmapped fields or lost connections in workflows using the macro. For example, we have a widely used macro for which we'd like to change the name of an input field, change it's default type from Date to DateTime, make it optional while keeping other fields mandatory. Currently, we cannot find a solution which would not require us to fix each workflow using the macro after changing it. We should be able to change the field names, field types (e.g. String to V_WString, Date to DateTime), select optional fields and do other modifications to Macro Input without having to update each workflow using the macro. The new Macro Input UI could be enhanced with a window similar to that of Select tool's. Technically, the Macro Input fields could have a unique ID by which they would be recognised in workflows, so the field names would just be aliases that could be changed without losing the mapping. In summary, we are restricted to our initial setup of Macro Input and it is very complicated to change it afterwards, especially if the macro is used widely.