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/router/cors.go

@@ -23,7 +23,6 @@ import (
 
 	"github.com/gin-contrib/cors"
 	"github.com/gin-gonic/gin"
-	"github.com/superseriousbusiness/gotosocial/internal/config"
 )
 
 var corsConfig = cors.Config{
@@ -81,7 +80,7 @@ var corsConfig = cors.Config{
 }
 
 // useCors attaches the corsConfig above to the given gin engine
-func useCors(cfg *config.Config, engine *gin.Engine) error {
+func useCors(engine *gin.Engine) error {
 	c := cors.New(corsConfig)
 	engine.Use(c)
 	return nil