Documentation missing!

[Lartu]

I'm back! I've been working on fixing old bugs and introducing new ones features. Here's a list of both new and old things that are missing documentation:

• Some functions that used to accept only one datatype now can take both text and numbers, so their documentation should be updated. They are the ones that use the $expression line-like value.
• The new FOR i FROM x TO y DO without STEP has yet to be documented.
• Same for CALL PARALLEL.
• The statements PUSH LIST and PUSH MAP have seemingly never been documented.
• The new ASCII escape character values have yet to be documented (such as ASCII_EOT and ASCII_FS).
• ERRORCODE and ERRORTEXT are not thread-safe and this should be documented.