We need a consistent file naming scheme

[kosloot]

A lot of modules (including those from foliautils assume certain file extensions for input, or create output with a predefined extension.

This is good to prevent modules from reading the wrong files. But is also very rigid.
And at the moment there are some inconsistencies. Which influences PICCL too.

So we need to overhaul this scheme once and for all (hopefully).

[kosloot]

This is closely related to:
https://github.com/LanguageMachines/foliautils/issues#23

An example is TICCL-chain, which makes files with the extension .chained but we want this as an input for FoLiA-correct, which demand an extension '.ranked'

[kosloot]

Merging in #27:
It would be desirable if all modules are capable of handling a (one?) filename prefix (including a PATH) and add their own suffixes on output.
Also the usage() and man pages should be clear about this.

This might (should?) also involve some FoLiA utils and the pipeline(s)