Add a script to download sbt if not present on the system

.gitignore

@@ -4,6 +4,7 @@
 *.iml
 *.iws
 .idea/
+.sbtlib/*.jar
 .settings
 .cache
 /build/

project/build.properties

@@ -15,4 +15,6 @@
 # limitations under the License.
 #
 
+# Note: If you change the sbt version please also change the sbt download
+# script in the root directory of the project called sbt.
 sbt.version=0.12.4

sbt

+#!/bin/bash
+# This script launches sbt for this project. If present it uses the system 
+# version of sbt. If there is no system version of sbt it attempts to download
+# sbt locally.
+SBT_VERSION=0.12.4
+URL1=http://typesafe.artifactoryonline.com/typesafe/ivy-releases/org.scala-sbt/sbt-launch/${SBT_VERSION}/sbt-launch.jar
+URL2=http://repo.typesafe.com/typesafe/ivy-releases/org.scala-sbt/sbt-launch/${SBT_VERSION}/sbt-launch.jar
+JAR=.sbtlib/sbt-launch-${SBT_VERSION}.jar
+
+printf "Checking for system sbt ["
+if hash sbt 2>/dev/null; then 
+    printf "FOUND]\n"
+    # Use System SBT
+    sbt
+else
+    printf "NOT FOUND]\n"
+    # Download sbt or use allready downloaded
+    if [ ! -d .sbtlib ]; then
+	mkdir .sbtlib
+    fi
+    if [ ! -f ${JAR} ]; then
+	# Download
+	printf "Attempting to fetch sbt\n"
+	if hash curl 2>/dev/null; then
+	    curl --progress-bar ${URL1} > ${JAR} || curl --progress-bar ${URL2} > ${JAR}
+	elif hash wget 2>/dev/null; then
+	    wget --progress=bar ${URL1} -O ${JAR} || wget --progress=bar ${URL2} -O ${JAR}
+	else
+	    printf "You do not have curl or wget installed, please install sbt manually from http://www.scala-sbt.org/\n"
+	    exit
+	fi
+    fi
+    if [ ! -f ${JAR} ]; then
+	# We failed to download
+	printf "Our attempt to download sbt locally to {$JAR} failed. Please install sbt manually from http://www.scala-sbt.org/\n"
+	exit
+    fi
+    printf "Launching sbt from .sbtlib\n"
+    java \
+	-Duser.timezone=UTC \
+	-Djava.awt.headless=true \
+	-Dfile.encoding=UTF-8 \
+	-XX:MaxPermSize=256m \
+	-Xmx1g \
+	-noverify \
+	-jar ${JAR} \
+	"$@"
+fi