TS: fixed single tag tuple name XML printing and reading, should be empty string and null reference.
TS: Move none TagOf case alternative guards into block as if statement (so they get into the correct scope and c printable).
TS: Initial support for multi tag tuples in the annotations and transformations, including support for the new StmtAlternative block.
TS: Initial support for the multi tag tuples in the c printing, including support for accessing the fields, type construction, variable tuple tag case statements, etc.