Our compat matrix mentions a couple of opcodes: ToInt, ToBlob, etc.
Those opcodes do not exist.
Instead, there is a single Cast opcode, that takes the affinity as a
parameter.
Currently we just call a function when we need to cast. This PR fixes
the compat file, implements the cast opcode, and in at least one
instance, when explicitly using the CAST keyword, uses that opcode
instead of a function in the generated bytecode.
4bd1582e7d