Update changelog for upcoming v5.0.0 release (#10)

Author: thomashoneyman

CHANGELOG.md

@@ -12,19 +12,27 @@ Bugfixes:
 
 Other improvements:
 
+## [v5.0.0](https://github.com/purescript-node/purescript-posix-types/releases/tag/v5.0.0) - 2021-MONTH-DAY
+
+Breaking changes:
+  - Added support for PureScript 0.14 and dropped support for all previous versions (#8)
+
+Other improvements:
+  - Migrated CI to GitHub Actions and updated installation instructions to use Spago (#7)
+  - Added a changelog and pull request template (#9)
+
 ## [v4.0.0](https://github.com/purescript-node/purescript-posix-types/releases/tag/v4.0.0) - 2018-05-26
 
-Updated for PureScript 0.12
+- Updated for PureScript 0.12
 
 ## [v3.0.0](https://github.com/purescript-node/purescript-posix-types/releases/tag/v3.0.0) - 2017-04-04
 
-Updates for 0.11 (@anilanar)
+- Updates for 0.11 (@anilanar)
 
 ## [v2.0.0](https://github.com/purescript-node/purescript-posix-types/releases/tag/v2.0.0) - 2016-10-21
 
 - Updated dependencies
 
 ## [v1.0.0](https://github.com/purescript-node/purescript-posix-types/releases/tag/v1.0.0) - 2016-06-11
 
-Updates for 1.0 core libraries and 0.9.1 compiler. This library will not work with compiler versions < 0.9.1.
-
+- Updates for 1.0 core libraries and 0.9.1 compiler. This library will not work with compiler versions < 0.9.1.