* esp32: Reinstate tmr.now() function using esp_timer_get_time()
Also added larger limit before wrapping if Lua's number type supports
it.
* Renamed tmr.now() to node.uptime()
Added second return value to indicate timer wrap
- Stop fighting against the SDK in terms of owning/writing the init_data block.
NodeMCU included a default init_data block because originally the SDK did
not, but by now it's not needed.
- Expose a way to reconfigure the ADC mode from Lua land. With most people
using the cloud builder and not able to change the #define for byte 107
this has been a pain point.
- Less confusion about which init_data has been used. Lua code can now simply
state what mode it wants the ADC to be in, and not worry about the rest of
the init_data complexities such as the init_data changing location due to
flashing with wrong flash_size setting, or doing/not doing a chip-erase
before loading new NodeMCU firmware.