[vsphere] check for string true/false instead of boolean

closes #2857
Release 1.22.0
[google|compute] Add Region tests
Enabled :path_style for Google Cloud Storage for allowing CNAME buckets
[google|compute] Update Images support

- Add missing "Image" properties
- Add "ready?" method to model
- Add "destroy" method to model
- Use "Operation" instead of the "backoff_if_unfound" method when inserting an "Image"
Merge pull request #2862 from frodenas/gce_images

[google|compute] Update Images support
Merge pull request #2872 from asanalabs/master

[google|storage] Enabled :path_style for Google Cloud Storage for allowing CNAME buckets
Merge pull request #2869 from frodenas/gce_region_tests

[google|compute] Add Region tests
[google|compute] Update Servers support

- Add missing "Server" properties
- Remove unnecessary property aliases
- When destroying a "Server" asyncronously return the "Operation" model instead of the raw operation response
- If zone is not set on "all" and "get" methods, use the list aggregated servers request (1 API call) instead of fetching all zones
- Add "list_aggregated_servers" request
- Fix "attach_disk" request
- Fix "detach_disk" request
- Add "get_server_serial_port_output" request
- Add "reset_server" request
- Add "set_server_disk_auto_delete" request
- Add "set_server_scheduling" request
- Add "add_server_access_config" request
- Add "delete_server_access_config" request
- Fix "set_tags" request