version bump and release opt level set to z
removed linter flag that wasn't useful
lints and cleanup

Removed unnecessary lifetime annotations
Moved Tweet::from_str to an impl of std::str::FromStr
Unignoring two tests that used to segfault cargo-tarpaulin
Changed some comparisons from .len() < 1 to is_empty()
moved to ureq for requests
updated doctest for parse::metadata so it no longer panics
using custom error type instead of string
changed metadata parse section:
if both metadata heading and keyword aren't in the file, return err
further check for improperly formatted statuses
updated crate metadata
cut some unnecessary code
added docs.rs badge
changed doc comments around
updated integ test
documentation added for new methods
changed structs api