Allow declaration of data type for session variables

[RADSr]

Being able to specify a data type for a session variable will save time/keystrokes/headaches when using the session variable in a formula - especially when used in conjunction with a function demanding a specific data type.

[marcpaige]

@RADSr, I asked for this a long time ago in the previous community. One great use case for this is using DATE data as the return. In order to use the session variable, you have to use the conversion function to use the value in date scenarios.