Release online-2.16

Changes:

• tools: add wch driver
• Jaguar is now v1.2.6 -- not beta (#141)
• tools: add support for Rust GNU and MSVC toolchain installation
• ci: Update builds with espressif-ide v2.6.0 and esp-idf v4.4.2 (#144)
• ci: add offline 4.4.2