There's an issue here - we can't remove 'is_unicode' since that is part of syntax... If 'is_unicode' is true it means that the value being put is binary data which contains UTF-16 encoded text... I think there was another branch that Panos did that interleaves with this (ServerOutput_1 I think) so it might be worth merging this with that and sorting it out.

The signatures of the Exec methods will need to change slightly:
```
MCServerExecPutContent(ctxt, MCStringRef)
MCServerExecPutUnicodeContext(ctxt, MCDataRef)
```
(or any similar, workable variant :))