Improve error reporting

[epsilon-phase]

When invoking file-freshener, it takes a rather horrifying route to error handling, it mostly doesn't.

This isn't acceptable, it should print messages about proper parameter usage. It also needs to check that the arguments for -insert for example aren't other commands like -freshen or redirect.

This would be easy enough to screen for, checking that the arguments do not start with a hyphen.

There are other things that are necessary, but this seems like it might be among the more important ones.

• [x] Add this to the insert command
• [ ] Add this to the replace command
• [ ] add this to the redirect command
• [ ] add this to the remove command.

[epsilon-phase]

I've added it to the insert command with 9c2b5fb. So far it needs a bit more work to really shine.