Add SecurityManagementPrivileges API client

[iorubs]

Add the following functions and corresponding tests:

• Retrieve a list of privileges.: GET /​beta​/security​/privileges
• Retrieve a privilege by id.: GET ​/beta​/security​/privileges​/{privilegeId}
• Delete a privilege by id.: DELETE /beta​/security​/privileges​/{privilegeId}
• Create an application type privilege.: POST ​/beta​/security​/privileges​/application
• Update an application type privilege.: PUT /beta​/security​/privileges​/application​/{privilegeId}
• Create a repository admin type privilege.: POST /beta​/security​/privileges​/repository-admin
• Update a repository admin type privilege.: PUT ​/beta​/security​/privileges​/repository-admin​/{privilegeId}
• Create a repository content selector type privilege.: POST ​/beta​/security​/privileges​/repository-content-selector
• Update a repository content selector type privilege.: PUT /beta​/security​/privileges​/repository-content-selector​/{privilegeId}
• Create a repository view type privilege.: POST /beta​/security​/privileges​/repository-view
• Update a repository view type privilege.: PUT ​/beta​/security​/privileges​/repository-view​/{privilegeId}
• Create a script type privilege.: POST ​/beta​/security​/privileges​/script
• Update a script type privilege.: PUT ​/beta​/security​/privileges​/script​/{privilegeId}
• Create a wildcard type privilege.: POST /beta​/security​/privileges​/wildcard
• Update a wildcard type privilege.: PUT ​/beta​/security​/privileges​/wildcard​/{privilegeId}