Handle import issue with urllib3 #377

[jasonacox]

User @Frefdt reported import error in #377:

ImportError: urllib3 v2.0 only supports OpenSSL 1.1.1+, currently the "ssl’ module is compiled with ‘OpenSSL 1.1.0h 27 Mar 2018". See: urllib3/urllib3#2168

TinyTuya uses the requests library which uses urllib3. It seems that v2 of urllib3 now requires OpenSSL 1.1.1 but some python environments only have OpenSSL 1.1.0. This PR updates the import requests of TinyTuya to gracefully handle this error.

try:
    import requests
except ImportError as impErr:
    print("WARN: Unable to import requests library, Cloud functions will not work.")
    print("WARN: Check dependencies. See https://github.com/jasonacox/tinytuya/issues/377")
    print("WARN: Error: {}.".format(impErr.args[0]))