#4 Context destructor

struct context* ctx = ink_make_deafult_context();

ink_destroy_context(ctx);

Create a way to destroy the conterxt from C while ensuring the complete cleanup of every element. ## Syntax From C: ```c struct context* ctx = ink_make_deafult_context(); ink_destroy_context(ctx); ``` ## Proposed implementation Clearing every coroutine manually, then clearing every `word` (due to #2), then running the GC should get rid of every reference still stored into the engine. We can then deallocate every remaining stack. ## Bounty 25€