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

testrig/email.go

@@ -18,7 +18,11 @@
 
 package testrig
 
-import "github.com/superseriousbusiness/gotosocial/internal/email"
+import (
+	"github.com/spf13/viper"
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+	"github.com/superseriousbusiness/gotosocial/internal/email"
+)
 
 // NewEmailSender returns a noop email sender that won't make any remote calls.
 //
@@ -26,6 +30,8 @@ import "github.com/superseriousbusiness/gotosocial/internal/email"
 // the map, with email address of the recipient as the key, and the value as the
 // parsed email message as it would have been sent.
 func NewEmailSender(templateBaseDir string, sentEmails map[string]string) email.Sender {
+	viper.Set(config.Keys.WebTemplateBaseDir, templateBaseDir)
+
 	var sendCallback func(toAddress string, message string)
 
 	if sentEmails != nil {
@@ -34,7 +40,7 @@ func NewEmailSender(templateBaseDir string, sentEmails map[string]string) email.
 		}
 	}
 
-	s, err := email.NewNoopSender(templateBaseDir, sendCallback)
+	s, err := email.NewNoopSender(sendCallback)
 	if err != nil {
 		panic(err)
 	}