Provide a showcase for print_commands.py and remove some old code

playground/display/wscript

@@ -1,8 +1,6 @@
 #! /usr/bin/env python
 # encoding: utf-8
-# Thomas Nagy, 2011 (ita)
+# Thomas Nagy, 2016 (ita)
-
-import sys
 
 def options(opt):
 	opt.load('compiler_c')
@@ -11,43 +9,6 @@ def configure(conf):
 	conf.load('compiler_c')
 
 def build(bld):
+	bld.load('print_commands')
 	bld.program(source='main.c', target='app')
 
-	customize_ze_outputs()
-
-def customize_ze_outputs():
-	# first, display strings, people like them
-	from waflib import Utils, Logs
-	from waflib.Context import Context
-	def exec_command(self, cmd, **kw):
-		subprocess = Utils.subprocess
-		kw['shell'] = isinstance(cmd, str)
-		if isinstance(cmd, str):
-			Logs.info('%s' % cmd)
-		else:
-			Logs.info('%s' % ' '.join(cmd)) # here is the change
-		Logs.debug('runner_env: kw=%s' % kw)
-		try:
-			if self.logger:
-				self.logger.info(cmd)
-				kw['stdout'] = kw['stderr'] = subprocess.PIPE
-				p = subprocess.Popen(cmd, **kw)
-				(out, err) = p.communicate()
-				if out:
-					self.logger.debug('out: %s' % out.decode(sys.stdout.encoding or 'iso8859-1'))
-				if err:
-					self.logger.error('err: %s' % err.decode(sys.stdout.encoding or 'iso8859-1'))
-				return p.returncode
-			else:
-				p = subprocess.Popen(cmd, **kw)
-				return p.wait()
-		except OSError:
-			return -1
-	Context.exec_command = exec_command
-
-	# and change the outputs for tasks too
-	from waflib.Task import Task
-	def display(self):
-		return '' # no output on empty strings
-	Task.__str__ = display
-