Create a section for parsing data

[evanfloden]

See examples:

https://github.com/seqeralabs/nf-training-public/tree/master/nf-training/parsing

[chriswyatt1]

Parsing section with examples has been added :https://github.com/seqeralabs/nf-training-public/blob/Autumn_update/asciidocs/parsing.adoc

Needs review and json module calling section