cosmetic improvements to code

- The version number didn't match at the top of the file and in the
  startup message.
- I actually started (and published) this program in 2012 -- fix
  copyright message to reflect that.
- Rewrap the help texts to use multiple print commands instead of a
  bunch of ugly \n's in the middle. The ugliness of that was absolutely
  not worth strict adherence to 80-character lines.
- Remove an import of a function that's not actually being used
  anywhere.
try to help users who don't see Anki open

Hopefully this way they know what to expect, and what they should do if
it doesn't work for some reason.
protect against file operations not working

Give a more friendly error when the user specifies a file that doesn't
exist, and in case the temporary file write fails.
use if __name__ == "__main__"

(on the off chance someone wants to use it as a module)
bump version and prepare for publish