Remove Task from Roc

[smores56]

Fully removes Task and the ! suffix from Roc. If you grep for it, there are only a couple places left where you'll find it:

• The website which should be updated separately
• In some already out-of-date docs in README's like test platforms, those should also be updated more comprehensively in a different PR
• Syntax tests that don't actually use Task to run code

Also, this re-removes the examples as was done in this PR after a merge failure caused them to be re-added.

[lukewilliamboswell]

Very nice 😄

Also tested this against basic-cli & basic-webserver with all tests ✅