Add option for automated cert in config process

This adds a new "Secure (port 443), auto certificate" option to the "Web
server mode" prompt when running `writefreely --config`. When chosen,
it'll set `autocert` to `true` and set the path for certs and keys to
`certs`.

Ref T542

config/setup.go

@@ -101,19 +101,23 @@ func Configure(fname string, configSections string) (*SetupData, error) {
 			selPrompt = promptui.Select{
 				Templates: selTmpls,
 				Label:     "Web server mode",
-				Items:     []string{"Insecure (port 80)", "Secure (port 443)"},
+				Items:     []string{"Insecure (port 80)", "Secure (port 443), manual certificate", "Secure (port 443), auto certificate"},
 			}
 			sel, _, err := selPrompt.Run()
 			if err != nil {
 				return data, err
 			}
 			if sel == 0 {
+				data.Config.Server.Autocert = false
 				data.Config.Server.Port = 80
 				data.Config.Server.TLSCertPath = ""
 				data.Config.Server.TLSKeyPath = ""
-			} else if sel == 1 {
+			} else if sel == 1 || sel == 2 {
 				data.Config.Server.Port = 443
+				data.Config.Server.Autocert = sel == 2
 
+				if sel == 1 {
+					// Manual certificate configuration
 					prompt = promptui.Prompt{
 						Templates: tmpls,
 						Label:     "Certificate path",
@@ -135,6 +139,11 @@ func Configure(fname string, configSections string) (*SetupData, error) {
 					if err != nil {
 						return data, err
 					}
+				} else {
+					// Automatic certificate
+					data.Config.Server.TLSCertPath = "certs"
+					data.Config.Server.TLSKeyPath = "certs"
+				}
 			}
 		} else {
 			data.Config.Server.TLSCertPath = ""