Implement Cobra CLI tooling, Viper config tooling (#336)

* start pulling out + replacing urfave and config

* replace many many instances of config

* move more stuff => viper

* properly remove urfave

* move some flags to root command

* add testrig commands to root

* alias config file keys

* start adding cli parsing tests

* reorder viper init

* remove config path alias

* fmt

* change config file keys to non-nested

* we're more or less in business now

* tidy up the common func

* go fmt

* get tests passing again

* add note about the cliparsing tests

* reorganize

* update docs with changes

* structure cmd dir better

* rename + move some files around

* fix dangling comma

internal/config/oidc.go

@@ -1,30 +0,0 @@
-/*
-   GoToSocial
-   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU Affero General Public License as published by
-   the Free Software Foundation, either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU Affero General Public License for more details.
-
-   You should have received a copy of the GNU Affero General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-package config
-
-// OIDCConfig contains configuration values for openID connect (oauth) authorization by an external service such as Dex.
-type OIDCConfig struct {
-	Enabled          bool     `yaml:"enabled"`
-	IDPName          string   `yaml:"idpName"`
-	SkipVerification bool     `yaml:"skipVerification"`
-	Issuer           string   `yaml:"issuer"`
-	ClientID         string   `yaml:"clientID"`
-	ClientSecret     string   `yaml:"clientSecret"`
-	Scopes           []string `yaml:"scopes"`
-}