update to the production release of Autoplot

[Jeremy Faden]

I've made an update to the production release of Autoplot, so ideally
everyone would upgrade.  This includes a number of fairly important
fixes, such as:

* some datasets provided by CDAWeb could not be used, including RBSP L4
density
* the draw grid option would cause all lines (including line plots) to
be drawn with a transparency, not opaque
* "where" used with CDF and aggregation would fail

There are some new features, such as:

* https file cache caches directory listings, allowing processes which
need only list slow remote directories to operate quickly
* add plots can add a stack of plots added to the right or left of the
current focus plot, making more complex layouts easier to form
* one JNLP now supports both 32 bit and 64 bit platforms, with the 64
bit getting 4GB of memory.
* PDS4 source now detects dependency between parameters

Let me know how this version works for you!  This is production version
v2021a_9 found with the "start Autoplot" link on http://autoplot.org. 
Enjoy!

Jeremy