Rework parameter flags

Closes #10

main.go

@@ -38,11 +38,11 @@ var (
 	// Envar OIDC has precedence over OIDC_AT
 	accessToken = app.Flag("at", "Access Token").Short('a').Envar("OIDC_AT").Envar("OIDC").Required().String()
 
-	issuerURIArg = app.Flag("issuer", "Issuer URI of your access token. Not needed if JWT access token with iss claim.").Short('i').Default("https://unity.helmholtz-data-federation.de/oauth2").String()
-	feudalURI    = app.Flag("uri", "Feudal URI").Short('u').Default("https://hdf-portal.data.kit.edu").String()
-	pubKey       = app.Flag("pubkey", "SSH public key file path").Short('k').String()
-	verboseArg   = app.Flag("verbose", "Increase verbosity").Short('v').Bool()
-	connectArg   = app.Flag("connect", "Open SSH connection, once credentials are received.").Short('c').Bool()
+	issuerURIArg = app.Flag("issuer", "Issuer URI of your access token. Not needed if JWT access token with iss claim.").Short('u').Default("https://unity.helmholtz-data-federation.de/oauth2").String()
+	feudalURI    = app.Flag("feudal", "Feudal URI").Short('f').Default("https://hdf-portal.data.kit.edu").String()
+	pubKey       = app.Flag("identity-file", "SSH identity (public key) file").Short('i').String()
+	verboseArg   = app.Flag("verbose", "Verbose output").Short('v').Bool()
+	connectArg   = app.Flag("connect", "Open SSH connection, once credentials are received (experimental).").Short('c').Bool()
 
 	issuerURI = ""