Support for configuring proxy exclusions

[zjs]

User Statement:

See vmware/vic#8144.

Details:

We should allow users to configure zero or more proxy exclusions near where they configure proxy settings for a VCH. Configuring proxy exclusions does not make sense if no proxy is configured.

Acceptance Criteria:

• [ ] Updated mockups
• [ ] Updated creation wizard
• [ ] Updated inspect/reconfigure dialog (or a child issue filed to track this)
• [ ] Appropriate automated testing

[lweitzman]

Updated mockups to allow for 1 or more proxy exclusions https://vmware.invisionapp.com/share/MUD5FRBS8#/239666133_Create_VCH_Wizard_-5_Network-_Advanced_2