Generate virtual/boards.txt from avr/boards.txt instead of linking them

When building the virtual boards, we want to have the base core as
`keyboardio:arduino`, instead of `arduino:arduino`, because we provide the base
ourselves. To this end, instead of symlinking `avr/boards.txt` and
`virtual/boards.txt`, generate the latter from the former.

Once we have other architectures, such as SAMD, we can concat all the boards.txt
files and do the same `base.core` replacements.

This is a pre-requisite for keyboardio/Kaleidoscope#851.

Signed-off-by: Gergely Nagy <algernon@keyboard.io>

.gitignore

@@ -1,2 +1,3 @@
 arduino-*-linux64.tar.xz
 arduino-*
+/virtual/boards.txt

.travis.yml

@@ -6,6 +6,7 @@ install:
 - mkdir -p ../hardware/
 - ln -s `pwd` ../hardware/keyboardio
 script:
+- make prepare-virtual
 - make travis-test-all BOARD_HARDWARE_PATH=$(pwd)/../hardware
 branches:
   except:

Makefile

@@ -27,6 +27,9 @@ KALEIDOSCOPE_BUILDER_DIR ?= ./avr/libraries/Kaleidoscope/bin/
 
 endif
 
+prepare-virtual:
+	sed -e "s/\(.*\)\.build\.core=arduino:arduino/\1.build.core=keyboardio:arduino/" avr/boards.txt >virtual/boards.txt
+
 update-submodules: checkout-submodules
 	@echo "All Kaleidoscope libraries have been updated from GitHub"
 

virtual/boards.txt

@@ -1 +0,0 @@
-../avr/boards.txt