🐾 When filter vms by host, make the host selection options instead of free text input

[yaacov]

Issue:
When filtering vms by host, a user need to write the name of the host using free text, we should allow easier way to select between hosts.

When filter vms by host, make the host drop-down or type-ahead input instead of free text input

Sub tasks:

• Make host selector use options - vmware provider
• Make host selector use options - ovirt provider

[yaacov]

addressed by #1274 and #1275