Mark --to and --amount flags required for gaiacli tx send

Closes: #2547

PENDING.md

@@ -202,6 +202,7 @@ BUG FIXES
 * Gaia CLI  (`gaiacli`)
     * [cli] [\#1997](https://github.com/cosmos/cosmos-sdk/issues/1997) Handle panics gracefully when `gaiacli stake {delegation,unbond}` fail to unmarshal delegation.
     * [cli] [\#2265](https://github.com/cosmos/cosmos-sdk/issues/2265) Fix JSON formatting of the `gaiacli send` command.
+    * [cli] [\#2547](https://github.com/cosmos/cosmos-sdk/issues/2547) Mark --to and --amount as required flags for `gaiacli tx send`.
 
 * Gaia
   * [x/stake] Return correct Tendermint validator update set on `EndBlocker` by not

x/bank/client/cli/sendtx.go

@@ -75,6 +75,8 @@ func SendTxCmd(cdc *codec.Codec) *cobra.Command {
 
 	cmd.Flags().String(flagTo, "", "Address to send coins")
 	cmd.Flags().String(flagAmount, "", "Amount of coins to send")
+	cmd.MarkFlagRequired(flagTo)
+	cmd.MarkFlagRequired(flagAmount)
 
 	return cmd
 }