Konstantin Kochin

The pull request contains the following changes: - support of the django 1.7 or lower has been dropped - support of the django 1.8-2.1 has been added - the south...

### Description The old `mbed-cli` tool supports [custom boards](https://os.mbed.com/blog/entry/Custom-and-community-board-support/) like [Bluepill](https://os.mbed.com/users/hudakz/code/mbed-os-bluepill/), but it doesn't allow to flash firmware and run [greentea](https://os.mbed.com/docs/mbed-os/v6.5/debug-test/greentea-for-testing-applications.html) tests on them, as some hardware debugger/programmers (like stlink...