Travis-CI: targets update, compilation matrix with sizes, documentation

scripts/travis-fill-cache.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+#
+# Download avr-gcc from Arduino and Microchip
+# Get also make 4 required to compile Optiboot
+#
+
+# path where tools are extracted
+LOCAL_TOOLS_DIR=$HOME/avr-tools
+
+
+# check if we are running by Travis-CI
+if [ -z "$TRAVIS_BUILD_DIR" ]; then
+    echo "This script should be run by Travis-CI environment"
+    echo "If you want to simulate Travis build, please set TRAVIS_BUILD_DIR"
+    echo "environment variable to directory where your code lives"
+    exit 1
+fi
+
+# include functions to download stuff
+. $TRAVIS_BUILD_DIR/scripts/travis-download.inc.sh
+
+# make directory for tools
+mkdir -p $LOCAL_TOOLS_DIR
+
+# get new make as Optiboot requires version >4.0
+download_make4
+
+# download Arduino versions
+for version in $(cat $TRAVIS_BUILD_DIR/docs/arduino-gcc-versions.md |grep -i "| yes |"|cut -f 2 -d '|'); do
+    download_arduino $version
+done
+
+# download Microchip's AVR8 Toolchain
+download_avr_toolchain