feat: add json schema

feat: add first version of json schema

todos: add arrays, add item

feat: add item to json schema

feat: add array types

add: json schema

fix: semver pattern

fix: URL pattern

feat: recursive metadata object

fix: file ref

fix: id base uri

feat: mime type pattern

feat: allow for xeno data, disallow any other

chore: move examples out of the specs

chore: move todos out of specs document

feat: add data integrity object to schema

fix: update requried sections

feat: validation script

fix: remove collector enfored role 'collector'

fix: version in sample data

Co-authored-by: @mrodzis <weidling@sub.uni-goettingen.de>

fix: metadata recursion

fix: json schema version

fix: path to item in sample

fix: copypaste flaws

fix: lang, format, typos

Co-authored-by: Michelle Weidling <weidling@sub.uni-goettingen.de>

doc: more precise desc on metadata recursion

fix: module description

fix: module description

feat: restrict support mime types