To fix jsdoor build

Helpful for scripts that want to know what file types (extensions) are
supported by the Archive class object.

Still need to work out the JSDOC support for this. Similar to the
Socket class object properties, this will have no documentation/description.

We need to set the "has pixels set" flag in both vmem and in the
bitmap_drawn array to prevent the update from erasing the pixels.

This is likely what the duplicated line was originally, then it got
broken when I switched to the vmem_cell_*() functions.

DDMsgReader: %% should be used with printf() to show a percent sign.  "% " seemed to be showing <error> in some cases (but not always)

See merge request !491

DDMsgReader: %% should be used with printf() to show a percent sign.  "% " seemed to be showing <error> in some cases (but not always)

We're building these one byte at a time, we know the length.
1.98s

For now we're still using strlen, but we can avoid the call for
the common case of zero-length returns.

2.1 seconds.

This should avoid angering Coverity.

Also, no, Coverity still doesn't know from recursive mutexes.

Thanks coverity!

They're all from accessing list values outside of a lock.
Lock the list earlier to include these.

Also, does this mean it knows they're recursive now?
Let's find out!

Make the one who opens it responsible for closing it.

This is a heavily accessed value that is rarely changed and was
causing a lot of contention on vstatlock.

Down to 2.9 seconds.

Derp.

Down to 3.4s now.

Fixes issue where returning to the main menu always takes you to
the top option.

The SSH input thread is too complex to easily make this change.

Coverity thinks it can do the default case.

Thanks Coverity!

Shaves time down to 3.85 seconds.

Fixes high CPU when nothing is happening.

SUB and DIR have long had this bug, but I just noticed while playing with the
new USER keyword capabilities (specifying user numbers and/or names).

If you switched between numeric and alpha/string parameters, without restating
the ARS keyword, the keyword would could end up wrong in the parsed byte array.

Caveat: the name parameter cannot contain a space, so excludes spaces or
replace them with '.' or '_': the user's alias will match.

This fixes issue #748