Environment#print_builder_run_message should support string commands - close #44

build_tests/build_dir/echo_command_ruby_builder.rb

@@ -0,0 +1,5 @@
+Rscons::Environment.new do |env|
+  env.echo = :command
+  env.Install("inst.exe", "install.rb")
+end
+

build_tests/build_dir/echo_command_string.rb

@@ -0,0 +1,13 @@
+class MyBuilder < Rscons::Builder
+  def run(options)
+    env, target = options.values_at(:env, :target)
+    env.print_builder_run_message("MyBuilder #{target}", "MyBuilder #{target} command")
+    target
+  end
+end
+
+Rscons::Environment.new do |env|
+  env.echo = :command
+  env.add_builder(MyBuilder.new)
+  env.MyBuilder("foo")
+end