3rd generation of knownset
updated the runtime test with a new pingpong test
test update
3rd knownset generation : Changed all structures + implemented 'PICC_create_empty_known' / 'PICC_create_known' as examples
rewriting knownset, no contracts for now
added some comments
Correct the runtime tests to use the new known set implementation + various bug fixes
added some macro for the backend
fix in channel and string value init
Refactor known set and add all the documentation
Add missing error messages
Add unit test for known sets and remove index_in_knownset from values
Add unit tests and bug fixes to known sets
Add contracts to known sets