update changelog

Fix daylight savings bug. Close #72

Ok, so I think this should actually address the problem once and for all. To be honest, I'm not quite sure what the previous code was trying to accomplish.

Previous work:
- #10
- #13
- 8fb2dee

We are no longer using `TimeZone.current` and `Locale.current` and attempting to figure out how to map the Cupertino Date to another location.

Instead we are using `PST` and `en-US` to specifically target the precise time zone and locale.

Update README.md

[3.0.0] release. bump version. update changelog.

update spec for 2.3.1

[2.3.0] release 2.3.0

Release 2.2.0

[CI] Fix danger, run pod lib lint (#16)

Close #14
Close #15

[2.0.1] update changelog and readme

cleanup