Merge pull request felipefialho#3 from kvnol/master

Add concrete solutions challenge

README.md

@@ -8,6 +8,18 @@ Listing some playful open-source's (just open-source! :warning:) challenges to v
 
 - [1STi](https://github.com/1STi/desafio-frontend/blob/master/README.md)
 - [Amaro](https://github.com/amarofashion/front-end-challenge)
+- [Catho](https://github.com/catho/frontend-test)
+- [Celular Direto](https://github.com/celular-direto/layout-front-end)
+- [Concrete Solutions](https://github.com/concretesolutions/recrutamento-fe)
+- [Contabilizei](https://github.com/contabilizei/front-end-teste)
+- [Creditas](https://github.com/Creditas/challenge/tree/master/frontend)
 - [DB Interativa](https://github.com/dbrinterativa/desafio_frontend)
 - [Din Digital](https://github.com/dindigital/teste-frontend-2017)
-- [Viva Real](https://github.com/vivareal/code-challenge/blob/master/frontend.md)
+- [Folha de SP](https://github.com/FolhaSP/front-end-test)
+- [iCasei](https://github.com/icasei/teste-front-end)
+- [iColabora](https://github.com/iColabora/teste-front-end-developer)
+- [Mkt Virtual](https://github.com/mktvirtual/front-end-test-wordpress)
+- [R7.com](https://github.com/r7com/frontend-test)
+- [Trampos](https://github.com/trampos/glowing-octo-batman)
+- [Viva Decora](https://github.com/vivadecora/front-end-teste)
+- [Viva Real](https://github.com/vivareal/code-challenge/blob/master/frontend.md)