Update changelog for 4.5 (#735)

* Update changelog for 4.5

* Update README with instructions for releases.

Looks like the right way to do a release is on GitHub itself and not
on the command line.

CHANGELOG.md

@@ -6,6 +6,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+## 4.5.0
+
+### Changed
+
+- Bumped a number of dependencies for security fixes
+
 ## 4.4.0
 
 ### Added
@@ -132,7 +138,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Fixed
 
 - Comparing dependency license contents now finds matching contents regardless of the order of the licenses (https://github.com/github/licensed/pull/516)
-- Fixed typo in a link in README.md (https://github.com/github/licensed/pull/514) 
+- Fixed typo in a link in README.md (https://github.com/github/licensed/pull/514)
 
 ### Changed
 

README.md

@@ -21,7 +21,7 @@ Licensed v3 includes a breaking change if both of the following are true:
 1. a project uses bundler to manage ruby dependencies
 2. a project uses the self-contained executable build of licensed
 
-All other usages of licensed should not encounter any major changes migrating from the latest 2.x build to 3.0.  
+All other usages of licensed should not encounter any major changes migrating from the latest 2.x build to 3.0.
 
 See [CHANGELOG.md](./CHANGELOG.md) for more details on what's changed.
 See the [v3 migration documentation](./docs/migrations/v3.md) for more info on migrating to v3.
@@ -94,7 +94,7 @@ To get started after checking out the repo, run
 
 You can also run `script/console` for an interactive prompt that will allow you to experiment.
 
-To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).
+To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then create a release on GitHub.
 
 ### Adding a new source