twee: Convert tabs to spaces

This was already done on "*.py", but the "twee" script doesn't have
a file extension.
twee: Print usage syntax when called without arguments

Previously, it would complain about no source files being specified
and would only print the usage syntax when argument parsing failed.

Also removed superfluous newline from "no source files" message.
twee: Removed adding "lib" dir to system path

There is no directory named "lib" in the Twine source tree.
twee: Force UTF8 output if stdout is redirected

The typical way of using "twee" is to redirect its output to an HTML
file. However, such a redirect will use ASCII encoding unless
overridden by the PYTHONIOENCODING environment variable. Therefore it
would break if the output contains Unicode characters.

To avoid that, check whether we are outputting to a tty or to a file
and in the latter case, explictly encode as UTF8 (with BOM).
Fixed displaying of long titles in PassageFrame
Merge pull request #126 from greyelf/i013_passage_title_fix

PassageFrame title field hides starting characters
Merge pull request #125 from mthuurne/twee_cleanup

Twee cleanup
Removed dependency from Twee on wxWidgets

Twee is a command line tool, so it shouldn't depend on a GUI toolkit.
However, the "tweelexer" module contained both GUI functionality and
essential non-GUI definitions. Solved this by splitting off the regex
definitions into the new module "tweeregex" and make Twee import that
instead.
Merge pull request #127 from mthuurne/twee_no_wx

TweeRegex module
StorySettings dialog scrollbars

* Added support for scrollbars in the StorySettings dialog, in case
custom story formats wish to add a lot of settings that necessitate a
longer window.
* Removed the "IE hack" from monospacedByLineHelper, after confirming
that it is not needed in IE 8.