System
* Allow "save picture of script with results" to work with the "say" block in "show advanced blocks" mode
* Convert WebThing server to a simple HTTP server
* Add ellipses to truncated strings  (> 800 bytes) returned from the board
* Update ESP32 binary boot and partition files (from PlatformIO)
* Improve reliability of Flashing ESP boards
* Change "is a" block default to number to make it clear that it works with the types in the "Operators" category
* Allow byte arrays to be included in the input list of "join items of list" block
* Prompt the user for file name when saving script images

Bug Fixes
* Fix: find primitive should return the Unicode character index, not the byte index
* Fix: Returning a ByteArray of length >= 936 crashes the VM
* Fix: Attempting to send long string (> 935 bytes) to the IDE causes the sending task to hang although other tasks continue to run
* Fix: ESPTool should re-enable auto-connect
* Fix: Update serial code for RTS/DTR handshaking to track recent changes to Serial API