A breaking change, but should finally see us move away from the chronic edge
cases and inconsistent behaviour we have while trying to shoe-horn the
usb-serial-jtag and cdc-acm consoles into uart behaviour and assumptions.
With the switch to use the IDF's stdin for feeding the Lua VM, we
unintentionally lost the ability to use uart.on('data') on the console uart.
This is since we no longer install the nodemcu uart driver on said uart.
In order to resolve this shortcoming, this commit refactors the uart.on('data')
delimiter handling and moves it away from platform.c into uart.c where it
really belongs. A new function, uart_feed_data(), is introduced, which is used
both by the nodemcu uart driver task as well as the nodemcu console driver
task (assuming the console is in fact a uart).
The linebuffer allocation/freeing is still in response to
uart.start()/uart.stop(), but it is now in uart.c rather than
platform.c.
The whole uart integration is still too tightly coupled between the platform
component and the module component's uart.c, but this makes it slightly
better at least.
The IDF provides all we need these days, and the old driver was just
needlessly conflicting with the IDF settings and setup.
This also simplifies our uart input path as we no longer need to
duplicate the raw byte handling for when "run_input" is false.
Changes have been kept to a minimum, but a serious chunk of work was
needed to move from 8266isms to IDFisms.
Some things got refactored into components/lua/common, in particular
the LFS location awareness.
As part of this work I also evicted our partition table manipulation
code, as with the current IDF it kept breaking checksums and rendering
things unbootable, which is the opposite of helpful (which was the
original intent behind it).
The uart module got relocated from base_nodemcu to the modules component
properly, after I worked out how to force its inclusion using Kconfig alone.