[meld] Update main script and README to indicate Python 2 requirement

[Kai Willadsen <kaiw src gnome org>]

commit 408919f04aad7949e35c8f5d0d7c22579a1a4595
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Tue Feb 25 06:56:11 2014 +1000

    Update main script and README to indicate Python 2 requirement

 README   |    1 +
 bin/meld |    4 ++++
 2 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/README b/README
index b9fd8e2..0c110a6 100644
--- a/README
+++ b/README
@@ -16,6 +16,7 @@ Meld is licensed under the GPL v2 or later.
 Requirements
 ------------
 
+* Python 2.7
 * GTK+ 3.6
 * GLib 2.34
 * PyGObject 3.8
diff --git a/bin/meld b/bin/meld
index 29f2754..97553cd 100755
--- a/bin/meld
+++ b/bin/meld
@@ -122,6 +122,10 @@ def check_requirements():
             print(_("Meld requires %s or higher.") % modver)
         sys.exit(1)
 
+    if sys.version_info[0] == 3:
+        print(_("Meld does not support Python 3."))
+        sys.exit(1)
+
     if sys.version_info[:2] < pyver:
         missing_reqs("Python", pyver)