Small issues in installer

[Andrea Spadaccini]

Hello everybody,
I just started using pwytter. I'm new to twitter and I love python,
and pwytter seems a cool client :D

I noticed two small issues in the installer:
1) the themes/ dir is not copied in the pwytter directory
2) the pwCache.py* files are not copied in the pwytter directory

Luckily it has been very easy to track down these small problems, but
they may be blockers for non-python users.

Thanks for the great client, I hope to see the minimize-to-tray
feature too, and maybe an integration with pyOSD (that would be really
easy to do)

Have a nice day,
Andrea