This refactors the request parsing, as well as improving the output for some request types. It also tweaks `yggdrasilctl` output, which should help with #947.
* Move yggdrasilctl responses to separate functions
* Move yggdrasilctl request switch to separate function
* Add empty lines
* Create struct CmdLine for yggdrasilctl
* Move yggdrasilctl command line parsing to separate func
* Turn struct CmdLine into CmdLineEnv
* Rename func parseCmdLine to parseFlagsAndArgs
* Move yggdrasilctl endpoint setting logic into separate func
* Function to create yggdrasilctl CmdLineEnv
* Reorder code
* Move struct fields into lines
* Turn yggdrasilctl CmdLineEnv funcs to methods
* Move yggdrasilctl connection code to separate func
* Rename functions
* Move yggdrasilctl command line env to separate mod
* Move yggdrasilctl command line env to main mod
* Run goimports
Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>
