[REF-1042] Hosting CLI: check the user selected app name

[martinxu9]

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• Bug fix (non-breaking change which fixes an issue)
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• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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• Check the user input against any characters not allowed in domain name, raise an error
• Clarify it is domain name safe characters when prompt for app name
• Remove the access token validation in hosting.deploy. It is not the first call to hosting server. Token is already validated. This can improve the speed on user with slow internet.
• If user input contains upper cases, print message informing user that the name is automatically converted to lower cases
• Example 1:

- Example 2: