use same src for Python 2 and 3

This is work is nearly complete. It works well on Python 3.3, but not 2.7. I get the following, which also results in empty output:

    $ liquidluck server
    [I 130418 21:27:34 generator:91] Load Settings Finished
    [E 130418 21:19:33 base:75] 'unicode' object is not callable
    ...snip same repeated message
    [E 130418 21:19:33 base:75] 'unicode' object is not callable
    [I 130418 21:19:33 generator:138] Load Posts Finished
    [I 130418 21:19:33 base:54] PostWriter Finished
    [I 130418 21:19:33 base:54] PageWriter Finished
    [I 130418 21:19:33 base:54] ArchiveWriter Finished
    [I 130418 21:19:33 base:54] ArchiveFeedWriter Finished
    [I 130418 21:19:33 base:54] FileWriter Finished
    [I 130418 21:19:33 base:54] StaticWriter Finished
    [I 130418 21:19:33 base:54] YearWriter Finished
    [I 130418 21:19:33 base:54] CategoryWriter Finished
    [I 130418 21:19:33 base:54] CategoryFeedWriter Finished
    [I 130418 21:19:33 base:54] TagWriter Finished
    [I 130418 21:19:33 base:54] TagCloudWriter Finished
    [I 130418 21:19:33 server:309] Theme directory: /home/tshepang/projects/liquidluck/liquidluck/_themes/default
    [I 130418 21:19:33 server:318] Start server at 127.0.0.1:8000