* Enabled ARM toolchain
* Cleaned unncessary stages
* Stages are defined inside compile and buildTestApps functions
* Added building of mbed-os-cliapp and mbed-client-testapp
  * These will build and test the mbed-os changes with all mbed-os-cliapp and mbed-client-testapp configurations, see Jenkinsfiles in https://github.com/ARMmbed/mbed-os-cliapp and https://github.com/ARMmbed/mbed-client-testapp for specifications