When compiling Janet with `JANET_REDUCED_OS`, `os/date` will not be available which breaks the tool amalg.janet. One can check file modification time on the filesystem instead.
A lot of refactoring larger integer types. Fix a number
of casting errors, but mostly rename things. Also try to
limit use of template-like macros as they bloat the binary
if not used in moderation. We were able to reduce the size of
typed array code as well by using a single view types.
This should speed up start time and reduce malloc/free
usage to about 15% of what is what previously for startup.
The current cost is slightly larger binary as the representaion
of the image is currently less compact than source code.
