mac_ai/ai.* should be generated automatically on build time. I do not
have access to mac machine to try it out, but I do not see any reason
for it not to work properly. Also, the files are obsolete because of
naming change anyway, so remove it.
Almost all python files in the project have shebang, but they are not
intended to be executed directly so remove the shebang if the file is
not intended to be executed directly. Set executable bit to files which
are meant to be executed directly.
Accidentally this also fixes bunch of trailing white-spaces as my editor
does that for me - bonus :). No actual code change included!