Clarify why we recommend entry points

[pfmoore]

Add a bit more details on why entry points are recommended rather than .py scripts or batch files. Include a mention of the limitations of PATHEXT on Windows and the difficulty for single-platform developers of maintaining robust cross-platform solutions.

[qwcode]

I thought the sentence we have now in the tutorial was pretty good: "the recommended approach to achieve cross-platform compatibility, is to use "console_script" entry points that register your script interfaces, and let the toolchain handle the work of turning these interfaces into actual scripts. "

[pfmoore]

Yeah, the problem that triggered this comment is that it doesn't explain why we recommend it. Unix guys don't have a problem, because scripts with an appropriate #! line are first-class citizens, but on Windows anything other than an actual .exe file will cause problems somewhere along the line.

I'll try and write some words.

[pfmoore]

See #54

[qwcode]

merged #54, closing

[pfmoore]

Thanks!