govc: Add sso.lpp.get and sso.lpp.update commands

[abonat]

Closes: #2975

Description

It extends govc functionality with GetLocalPasswordPolicy and UpdateLocalPasswordPolicy methods, which are already here.
The new sso.lpp.get and sso.lpp.update commands are available
Tools like Ansible can read the state before do any change.
The check mode in Ansible modules can work also.

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

How Has This Been Tested?

• sso.lpp.get

Description: The Number Of The Beast
MinLength: 0
MaxLength: 1
MinAlphabeticCount: 0
MinUppercaseCount: 0
MinLowercaseCount: 0
MinNumericCount: 0
MinSpecialCharCount: 0
MaxIdenticalAdjacentCharacters: 1
ProhibitedPreviousPasswordsCount: 1
PasswordLifetimeDays: 666

• sso.lpp.update
  govc sso.lpp.update -PasswordLifetimeDays 0 -Description "The Great Zeroing"
• sso.lpp.get - json
  { "LocalPasswordPolicy": { "Description": "The Great Zeroing", "ProhibitedPreviousPasswordsCount": 1, "PasswordFormat": { "LengthRestriction": { "MinLength": 0, "MaxLength": 1 }, "AlphabeticRestriction": { "MinAlphabeticCount": 0, "MinUppercaseCount": 0, "MinLowercaseCount": 0 }, "MinNumericCount": 0, "MinSpecialCharCount": 0, "MaxIdenticalAdjacentCharacters": 1 }, "PasswordLifetimeDays": 0 } }

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

[dougm]

Thanks @abonat , looks good, just a few minor suggestions

[dougm]

Thanks @abonat