Polish

[yoshuawuyts]

Applies a much needed layer of polish to Hypercore. Among other things it makes building Hypercore instances a lot more ergonomic, and fixes the existing failures.

This is a bit of an "everything" patch because, well, nobody is working actively on Hypercore at the moment so I figured there'd be little harm in just creating a big ol' patch to add all changes (and get back to making dependabot happy).

Code Example

let mut feed = hypercore::open("./feed.db")?;

feed.append(b"hello")?;
feed.append(b"world")?;

assert_eq!(feed.get(0)?, Some(b"hello".to_vec()));
assert_eq!(feed.get(1)?, Some(b"world".to_vec()));

Changes

• updated to rust 2019
• upgraded dependencies
• updated to standard rust fmt formatting
• added hypercore::open
• renamed Feed::new to Feed::open to be consistent with std::fs::File, and pass the clippy lint

Related Patches

• depended on add parts accessor methods merkle-tree-stream#25
• closes 73-update-random-access-crates #76

[yoshuawuyts]

Going to go ahead and merge these changes (: