Add Examples section to documentation

[jimmyfrasche]

Need at least one example per input mode.

Examples need to take up as few lines as possible, but have complete inputs, outputs, and specifications, while still being easily readable.

Examples should rely on common tools only (other than txt itself).

Copying and pasting the input and specification should produce the same or similar output.

If there are any really good examples that are too big or complex to meet the above criteria an examples/ directory can be created.