recommend GhPro as a replacemetn for custom tools

tools/backport_pr.py

@@ -161,6 +161,10 b" def should_backport(labels=None, milestone=None, project='ipython/ipython'):"
 
 if __name__ == '__main__':
     project = 'ipython/ipython'
+
+    print("DEPRECATE: backport_pr.py is deprecated and is is now recommended"
+          "to install `ghpro` from PyPI.", file=sys.stderr)
+
     args = list(sys.argv)
     if len(args) >= 2:
         if '/' in args[1]:

tools/github_stats.py

@@ -110,6 +110,10 b' def report(issues, show_urls=False):'
 #-----------------------------------------------------------------------------
 
 if __name__ == "__main__":
+
+    print("DEPRECATE: backport_pr.py is deprecated and is is now recommended"
+          "to install `ghpro` from PyPI.", file=sys.stderr)
+
     # deal with unicode
     if sys.version_info < (3,):
         sys.stdout = codecs.getwriter('utf8')(sys.stdout)