This changes the containing dir name to match the fileutils package name.

This simplifies logging and logging/exiting, plus supports the -v flag
for showing verbose output.

A lot has changed to the previously named codegangsta/cli library, and
this gets up to date with everything, fixing issue #8.

It also passes around errors from funcs that perform actions inside the
command funcs, for more Go-ness.

- Adds comments where necessary
- Fixes some variable names
- Fixes if/else statements with returns
- Use fmt.Errorf(...)

Found while going over new functionality (#6)

Keeps temporary post file around until a post successfully goes through.

Fixes the start command.
Saves the temporary file with .txt extension, so that Windows can correctly handle it.

Creates a new temporary file and posts whatever was written to it once
the user exits their editor.

TODO: don't lose work if something goes wrong in the posting process

Includes --id and --url flags for customizing the output

So the executable will be named "writeas"

Plus only show post URL upon success