Add CHANGELOG and Contributors to README file

CHANGELOG.md

+# CHANGELOG
+
+## v1.1.2 - 26-05-2019
+- Various styling fixes, UI improvements, license and documentation improvements before making the project Open Source 🎉
+
+## v1.1.1 - 22-05-2019
+- Added testimonals to home page with [this commit](https://gitlab.com/kodilan/frontend/commit/a4c7ace3db10163c059dba0a40f1ca4b142aed57)
+
+## v1.1.0 - 17-04-2019
+- Implemented show related jobs in job details page feature with [this commit](https://gitlab.com/kodilan/frontend/commit/64973cf7044a1ca974e50a6a046f36bf7112a55e)
+
+## v1.0.2 - 05-03-2019
+- Implemented company posts page by [Didem Acet](https://gitlab.com/didemacet) with [this commit](https://gitlab.com/kodilan/frontend/commit/8754a7d798c652dd171a8dda65e315e2796cf2ba) 👍
+
+## v1.0.1 - 04-03-2019
+- Implemented Axios Cache Middleware with [this commit](https://gitlab.com/kodilan/frontend/commit/630edf1a37e47e634ec8bbb8f78311021235d06a)
+
+## v1.0.0 - 18-02-2019
+- 🎉 Initial release [*](https://twitter.com/fatihacet/status/1097484925685649408)

README.md

@@ -23,6 +23,16 @@ We use [yarn](https://yarnpkg.com/en/) as our package manager and you should hav
 - yarn install
 - yarn serve
 
+### CHANGELOG
+
+Please take a look at the [CHANGELOG](https://gitlab.com/kodilan/frontend/blob/master/CHANGELOG.md) file.
+
+### Contributors
+
+- [Fatih Acet](https://twitter.com/fatihacet)
+- [Emir Karşıyakalı](https://twitter.com/emirkarsiyakali)
+- [Didem Acet](https://twitter.com/didemacet)
+
 ### More content
 
 You can take a look the following video to deep dive into the codebase.