Platform Intel Mcs51 Versions Save

• Updated SDCC toolchain to v4.4.0 (#54)
• Updated STC MCU ISP flash tool to v1.10 (#56)
• Minor fixes and improvements (#57)

Thanks @hhgyu for your contribution!

• Added compatibility with PIO Core 6.0

• Added support for our 250+ target devices (AT89***, IAP***, IRC***, ML***, N7***, STC***, W79***)
• Added initial support for CH559 (WIP/RFC) (issue #29)
• Updated SDCC toolchain to the v4.2.0 (issue #35)
• Uppercase board manifest name for the target devices

• Remove hardcoded "python3" form upload command (issue #34)

• New board "Generic STC15F2K60S2"

• Add Generic STC89C52RC

• Added "stcgal_protocol" field which you can override via board_upload.stcgal_protocol = *** (issue #16)
• Updated SDCC toolchain to 3.8.4#10766
• Fixed warning about "Unknown upload protocol custom"

• Add STC examples (issue #15)
• Add Generic STC15W204S (issue #14)
• Fix issue with invalid path to tool-stcgal

• Initial support