Added licenses types for python packets to LICENSE.md, updated versions definition in requirements.txt

LICENSE.md

@@ -54,3 +54,6 @@ The Python modules used by Mbed tools are used under the following licenses:
 - [pywin32](https://pypi.org/project/pywin32/) - PSF
 - [wmi](https://pypi.org/project/WMI/) - MIT
 - [psutil](https://pypi.org/project/psutil/) - BSD
+- [click](https://pypi.org/project/click/) - BSD-3-Clause
+- [cryptography](https://pypi.org/project/cryptography/) - BSD, Apache-2.0
+- [jwcrypto](https://pypi.org/project/jwcrypto/) - LGPLv3+

requirements.txt

@@ -26,7 +26,7 @@ cmsis-pack-manager>=0.2.3,<0.3.0
 pywin32==224;platform_system=='Windows'
 wmi==1.4.9;platform_system=='Windows'
 psutil==5.6.2
-cryptography>=2.4.2
-Click>=7.0
-jwcrypto>=0.6.0
+cryptography>=2.4.x,<2.5
+Click>=7.0,<7.1
+jwcrypto>=0.6,<0.7
 pathlib>=1.0.1