Removed uppercase characters. Don't like the mixture of lowercase and…

… uppercase characters in a tinchy URL; tinchy URLs should work aurally too.

tinchy.py

@@ -1,7 +1,7 @@
 import bottle, random, shelve
 
 def generate_tinchy_id():
-    return ''.join(random.sample('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890', 3))
+    return ''.join(random.sample('abcdefghijklmnopqrstuvwxyz1234567890', 3))
 
 @route('/')
 def index():