Make: use xcpretty if available.

Makefile

@@ -1,12 +1,19 @@
+BUILDCLEANER := xcpretty
+TESTCLEANER := xcpretty
+ifeq (,$(shell command -v xcpretty))
+	BUILDCLEANER := egrep '^(/.+:[0-9+:[0-9]+:.(error|warning):|fatal|===)'
+	TESTCLEANER := egrep -v '^Test Suite|^Test Case|^\t Executed'
+endif
 
 .PHONY: build test clean
 
-build: 	
-	@xcodebuild | egrep '^(/.+:[0-9+:[0-9]+:.(error|warning):|fatal|===)' -
+build: 
+	@xcodebuild | ${BUILDCLEANER}
 
 test: build
-	@xcodebuild test -scheme SwiftShell | egrep -v '^Test Suite|^Test Case|^\t Executed '
+	@xcodebuild test -scheme SwiftShell | ${TESTCLEANER}
 	
+	@echo
 	@echo "=== RUN SwiftShell TEST SCRIPTS (SwiftShellTests/Scripts/runtests.bash) ==="
 	@cd ./Tests/Scripts/ && ./runtests.bash 
 	@echo