Catch assets without file extensions

Based on the log file we got where it would hang ~97%
At the bottom was this:
2014-02-22 05:08:41,878 DEBUG      File "build\assets.py", line 322, in
index_data
2014-02-22 05:08:41,878 DEBUG    IndexError: list index out of range

line 322 was category = os.path.basename(asset[0]).split(".")[1]

This would return index out of bounds if there wasn't a period in the
key. Changed the line to splittext which will return a 2-tuple, index 0
is the filename index 1 is the "last extension"

Added the warning about assets that don't have extensions so modders can
fix them.
Merge pull request #68 from Septarius/dev

Catch assets without file extensions
Remove manual select player, fixes #61
Stop setting species to dummy on empty value
Add support for import player JSON files

I've decided to go with a dict update instead of full overwrite, I think
it would be cool to allow importing partial player files
Make mainwindow widgets update values immediately

This also fixes bugs with exporting not using current values
Add codex items to index
Remove status effects button

Won't work :(
Been playing around with this, any changes to the active status
list is immediately updated. Works fine adding effects to items
though so something to consider when working on that
Remove play time stuff, update mainwindow gui

So it doesn't really do anything even with persist crops. I've just
taken out the gui part of play_time and rearranged the form a little
Fix . in categories

new function asset_category takes care of this now.
Load Vanilla images in mods

Should Fix #70
If the mod requests an image doesn't exist try loading it from vanilla
assets before giving up.
If we need to load vanilla JSON also just remove the image checks.
It also converts the key for file system mods that would access packed
vanilla assets.
Initial tech management support

- Indexes techs but no metadata (it may not be required, we need to lookup
  the .techitem files for tech info anyway)
- Shows tech management dialog but doesn't do anything yet
Update README, moving to starcheat.org

I WILL ADD COMMENTS. EXCITING
:/
Get ready for release

- Bumped config version
- Bumped version (and set a real one!)
- Updated screenie
- Disable tech button again (temporary)