Split platformio.ini into one file for each board, only leaving platform definitions and a handful of stale (?) boards around.. (#1141)

variants/t-echo/platformio.ini

@@ -0,0 +1,17 @@
+; First prototype eink/nrf52840/sx1262 device
+[env:t-echo]
+extends = nrf52840_base
+board = t-echo
+debug_tool = jlink
+upload_protocol = jlink
+# add our variants files to the include and src paths
+# define build flags for the TFT_eSPI library - NOTE: WE NOT LONGER USE TFT_eSPI, it was for an earlier version of the TTGO eink screens
+# -DBUSY_PIN=3 -DRST_PIN=2 -DDC_PIN=28 -DCS_PIN=30
+# add -DCFG_SYSVIEW if you want to use the Segger systemview tool for OS profiling.
+build_flags = ${nrf52840_base.build_flags} -Ivariants/t-echo 
+src_filter = ${nrf52_base.src_filter} +<../variants/t-echo>
+lib_deps = 
+  ${nrf52840_base.lib_deps}
+  https://github.com/geeksville/GxEPD2.git
+  adafruit/Adafruit BusIO
+;upload_protocol = fs