Merge SimplicityHL examples?

[imaginator]

Describe the feature

I notice that we also have https://github.com/BlockstreamResearch/SimplicityHL/tree/master/examples and we have a repo called "Simplicity contracts" - somewhat confusing. Would it make sense to migrate the HL examples in here? @schoen?

[KyrylR]

Those contracts are related to the state management and options, which should be ideally tested, but for me it make sense as well to move those to the SimplicityHL examples as well

[KyrylR]

Thought, here we have quite a nice history of reviewing those (I mean options and byte32 storage) by @apoelstra and @roconnor-blockstream