tweak build targets

Makefile

@@ -1,5 +1,9 @@
-.PHONY: default
-default:
+.PHONY: all
+all:
+	@rake $@
+
+.PHONY: library
+library:
 	@rake $@
 
 .PHONY: gui

Rakefile.rb

@@ -47,7 +47,9 @@ task :test => :library do
   system("./build/tests")
 end
 
-task :default => [:library]
+task :default => :all
+
+task :all => [:library, :gui]
 
 task :clean do
   Rscons.clean