Add a new type of cluster action

[pranshujain28]

Add a new type of cluster action.

Description

Add a new type of cluster action used for placing a VM. This action inherits from InitialPlacement action because it conveys the resource pool and host for placing the VM. In addition, it also has the VM's ConfigSpecwhich is used for indicating the recommended datastore for each virtual disk in VM's ConfigSpec.

Type of change

Please mark options that are relevant:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to
  not work as expected)
• This change requires a documentation update
• Build related change

Checklist:

• My code follows the CONTRIBUTION guidelines of
  this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged

[vmwclabot]

@pranshujain28, you must sign our contributor license agreement before your changes are merged. Click here to sign the agreement. If you are a VMware employee, read this for further instruction.

[vmwclabot]

@pranshujain28, your company's legal contact has approved your signed contributor license agreement. It will also be reviewed by VMware, but the merge can proceed.

[dougm]

lgtm, thanks @pranshujain28

[embano1]

nit: next time please adhere to the CONTRIBUTING guidelines wrt commit message naming, prefixes, linking issues and squashing commits so your contributions are rendered nicely in all changelogs ,)

For example, we have api: as a prefix for such API related changes.

[vmwclabot]

@pranshujain28, VMware has rejected your signed contributor license agreement. The change has already been merged, but it will be backed out by the project maintainers if the agreement is not resigned in a timely manner. Click here to resign the agreement.