Some fixes for supporting python3

* Fix imports.
* Use python3 syntax.
* Wrap map() calls with list().
* Use list() only wherever needed.
  (Thanks Conley!)
* Fix dictionary iteration methods
  (s/iteritems/items/).
* Make use of sorted() in appropriate places
* Use iterators directly in the loop.
* Don't use .keys() wherever it isn't needed.
* Use sys.maxsize instead of sys.maxint

TODO:
* Make repo work fully with python3. :)

Some of this was done by the '2to3' tool [1], by
applying the needed fixes in a way that doesn't
break compatibility with python2.

Links:
[1]: http://docs.python.org/2/library/2to3.html

Change-Id: Ibdf3bf9a530d716db905733cb9bfef83a48820f7
Signed-off-by: Chirayu Desai <cdesai@cyanogenmod.org>

subcmds/help.py

@@ -34,8 +34,7 @@ Displays detailed usage information about a command.
   def _PrintAllCommands(self):
     print('usage: repo COMMAND [ARGS]')
     print('The complete list of recognized repo commands are:')
-    commandNames = self.commands.keys()
-    commandNames.sort()
+    commandNames = list(sorted(self.commands))
 
     maxlen = 0
     for name in commandNames:
@@ -55,10 +54,9 @@ Displays detailed usage information about a command.
   def _PrintCommonCommands(self):
     print('usage: repo COMMAND [ARGS]')
     print('The most commonly used repo commands are:')
-    commandNames = [name
-                    for name in self.commands.keys()
-                    if self.commands[name].common]
-    commandNames.sort()
+    commandNames = list(sorted([name
+                    for name, command in self.commands.items()
+                    if command.common]))
 
     maxlen = 0
     for name in commandNames: