This patch adds new constructors for MCError, allowing varargs or va_list forms.

This patch checks to see if the the source and target typeinfos are
the same before doing any further analysis.

This patch contains a significant rework of the LCB VM implementation.

Most notably, individual bytecodes are now described as individual structs,
and the main operations of description (for building), validation and
execution for each bytecode is within the struct.

In order to ensure iterators still work in the new VM, some tweaks were
necessary to the standard library implementations.

The VM needs to be able to check for conformance at times when it
doesn't have access to the type names.

This is required to resolve ambiguity when both sides are undefined.

This overload was ambiguous and could never be called because the chars
form was always chosen instead.

Otherwise, it isn't possible to use uninitialised vars for the
iteration variable.

The case where both were the same (foreign) type wasn't handled.

The case of unbridgeable foreign types (like pointer) wasn't handled so
optional forms of these types weren't usable as parameters as they'd
fail due to the lack of bridging from undefined -> pointer.

Auto-converion of foreign types now happens if they are the same type
or if they share a bridging type. Without this, there is no way to
convert between different types of C integers.

This fixes inout/out parameters misbehaving in some circumstances.

It now handles any foreign type that bridges to MCNumberRef, not just
NumberRefs themselves. This fixes problems when lists contain foreign
number types (like C floats or integers).

The failure to bridge is properly detected.

The parameter is only used on X11 and is null everywhere else.

There isn't yet the capability to have default initialisers for custom
types.

It needs to be checked against the special value kMCNullTypeInfo.

This reverts commit d581be6.

The underlying cause has been fixed so this assertion can be reinstated.

Not bridging here complicates implementations of various things as they
have to do the conversions themselves.

This reverts commit eab3813.

Conflicts:
	libscript/src/codeunit.lcb