cmdline-opts: added some missing info

docs/cmdline-opts/egd-file.d

@@ -1,4 +1,5 @@
 Long: egd-file
+Arg: <file>
 Help: EGD socket path for random data
 Protocols: TLS
 See-also: random-file

docs/cmdline-opts/form-string.d

@@ -1,6 +1,7 @@
 Long: form-string
 Help: Specify HTTP multipart POST data
 Protocols: HTTP
+Arg: <name=string>
 See-also: form
 ---
 Similar to --form except that the value string for the named parameter is used

docs/cmdline-opts/quote.d

@@ -1,4 +1,5 @@
 Long: quote
+Short: Q
 Help: Send command(s) to server before transfer
 Protocols: FTP SFTP
 ---

docs/cmdline-opts/referer.d

@@ -1,5 +1,6 @@
 Long: referer
 Short: e
+Arg: <URL>
 Protocols: HTTP
 Help: Referer URL
 See-also: user-agent header