powershell instructions did not work when mukltiple ssh keys were configured.

Also ignoring empty lines in the input.

.idea/.gitignore

@@ -1,8 +0,0 @@
-# Default ignored files
-/shelf/
-/workspace.xml
-# Editor-based HTTP Client requests
-/httpRequests/
-# Datasource local storage ignored files
-/dataSources/
-/dataSources.local.xml

pkg/server/ui/usageinputs.go

@@ -2,6 +2,7 @@ package ui
 
 import (
 	"fmt"
+	"strings"
 )
 
 type UsageInputs struct {
@@ -38,12 +39,21 @@ func addSshKeys(shell Shell, keys []string) string {
 	}
 	res := ""
 	for index, key := range keys {
+		key = strings.TrimSpace(key)
+		if key == "" {
+			continue
+		}
 		operator := ">>"
 		if index == 0 {
 			operator = ">"
 		}
 		if shell == POWERSHELL {
-			res += fmt.Sprintf(`"%s" | Out-File -FilePath ".authorized_keys" -Encoding ASCII<br/>`, key)
+			append := ""
+			if index > 0 {
+				append = "-Append "
+			}
+			res += fmt.Sprintf(`"%s" | Out-File %s-FilePath ".authorized_keys" -Encoding ASCII<br/>`,
+				key, append)
 		} else {
 			res += fmt.Sprintf("        echo %s%s%s %s .authorized_keys<br/>", quote, key, quote,
 				operator)