Mbed-cli

New features

https://github.com/ARMmbed/mbed-cli/pull/964 Enable flash option with dual core targets

Fixes

- Removed mercurial from the dependency list so that it does not block installation on Windows if Visual C++ compiler is not installed: 962 944. However, `mercurial` remains a requirement.

New features

940

Fixes
* 924 Print tip only if verbose it not used.
* 926 Update to generic tests.

New features
* 919 931 937 939 Python 3 support.

Other changes
* Minimum Python 3 version supported is 3.5, 2.7 continues to be supported.

Fixes
* Improved python-3 support
* 889 Removed a warning generated when parsing the python requirements file
* 890 Fix support for 'latest' and 'tip' tags in .lib files
* 896 Git now uses the branch that the cache was checked out to, rather than master, by default. This then follows the selection of 'default branch' as understood by github
* 903 Removed unsupported --profile option when calling get_config.py
* 907 get_config now reports the actual built config, even when app_config != mbed_app.json.

New features
* 900 Improved warning messages around python-3 support.
* 884 Platform detection now uses mbedls rather than older detect code

Other changes
* Now dependent on mbed-os-tools and pyserial
* Minimum version of Python now explicitly declared.

Fixes
* 870 Use `input()` instead of `raw_input()` for py3
* 874 Add `decode` call to icetea application list output

New features
* 873 allow tag to be used in mbed import

Fixed
* 850 Don't overwrite `mbed_app.json` on newly imported projects
* 857 Stream downloads of mbed 2 zip files. Prevents Out of memory(OOM) errors
* 865 Improve help of `mbed config` subcommand
* 866 Correct python3 handling of .lib files