PDI-1836: Add configuration profiles capability

[erikostien-pingidentity]

• Create a profiles package intended to manage Viper configuration profiles.
• Create profiles/types.go to manage configuration Option types which link the cobra parameter name, viper key,
  environment variable, and variable type together. Additional utility functions were added to access data from Options.
• Create profiles/validate.go to validate .pingctl/config.yaml configuration file, including each profile individually. Profile names must be alphanumeric plus dashes or forward slashes. This replaces the previous validate.go file.
• Create profiles/viper.go to create, manage, and change viper instances. Viper instances are used to scope configuration
  to a specific profile while maintaining the main configuration file. It also adds the notion of deferred binding of env vars and flags, so the user-chosen profile can bind them after initialization (See root.go OnInitialize()).
• Update multiple tests to use the Option type to retrieve viper key information.
• Update output functions and Opts type to follow Golang's best practices on repetition and naming.
• Transition all config get/set/unset commands to use new profile viper instance.
• Update PingOne provider test version to 1.0.0-rc2.

[henryrecker-pingidentity]

Just a few very small comments, looks good to me otherwise