Add install riscv gcc and setup script

install_riscv_gcc.sh

@@ -0,0 +1,57 @@
+#!/bin/bash
+
+
+uname="$(uname -s)"
+unameM="$(uname -m)"
+fileHeader="gnu-mcu-eclipse-riscv-none-gcc-7.2.0-2-20180111-2230-"
+urlHeader="https://github.com/gnu-mcu-eclipse/riscv-none-gcc/releases/download/v7.2.0-2-20180110/"
+installPath=gnu-mcu-eclipse/riscv-none-gcc/7.2.0-2-20180111-2230
+binFile=$installPath/bin/riscv-none-embed-gcc
+
+if [ -e $binFile ]
+then
+    echo "Riscv-gcc has been installed."
+    echo "To uninstall riscv-gcc, use 'make uninstall-gcc'."
+    exit 0
+fi
+
+echo "Downloading riscv-gcc..."
+case $uname in
+    Linux*)
+        if [ $unameM = "x86_64" ]; then
+            file=$fileHeader"centos64.tgz"
+        else
+            file=$fileHeader"centos32.tgz"
+        fi
+        curl -# -L -O $urlHeader$file
+        ;;
+    Darwin*)
+        file=$fileHeader"osx.tgz"
+        curl -# -L -O $urlHeader$file
+        ;;
+    CYGWIN*)
+        if [ $unameM = "x86_64" ]; then
+            file=$fileHeader"centos64.tgz"
+        else
+            file=$fileHeader"centos32.tgz"
+        fi
+        curl -# -L -O $urlHeader$file
+        ;;
+    MINGW32*)
+        echo "MINGW32 not supported yet."
+        exit 1
+        ;;
+    MINGW64*)
+        echo "MINGW64 not supported yet."
+        exit 1
+        ;;
+    *)
+        echo "UNKNOWN:$uname"
+        exit 1
+esac
+
+tar xf $file
+rm -f $file
+#chmod -R -w $installPath
+cd ..
+echo "Riscv-gcc has been installed."

setup.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+export PATH=$(pwd)/gnu-mcu-eclipse/riscv-none-gcc/7.2.0-2-20180111-2230/bin/:$PATH