make sidebar titles nicer

docs/gaia/join-testnet.md

@@ -1,4 +1,4 @@
-# Join the latest public testnet
+# Join Public Testnet
 
 ::: tip Current Testnet
 See the [testnet repo](https://github.com/cosmos/testnets) for

docs/gaia/ledger.md

@@ -1,4 +1,4 @@
-# Ledger // Cosmos
+# Ledger Nano Support
 
 ### Ledger Support for account keys
 

docs/gaia/validators/security.md

@@ -1,4 +1,4 @@
-## Overview
+## Validator Security
 
 Each validator candidate is encouraged to run its operations independently, as diverse setups increase the resilience of the network. Validator candidates should commence their setup phase now in order to be on time for launch.
 
@@ -49,4 +49,4 @@ By default, uppercase environment variables with the following prefixes will rep
 - `BC` (for democli or basecli flags)
 
 For example, the environment variable `GA_CHAIN_ID` will map to the command line flag `--chain-id`. Note that while explicit command-line flags will take precedence over environment variables, environment variables will take precedence over any of your configuration files. For this reason, it's imperative that you lock down your environment such that any critical parameters are defined as flags on the CLI or prevent modification of any environment variables. 
-  
+  

docs/gaia/validators/validator-setup.md

@@ -1,4 +1,4 @@
-# Run a validator on the gaia public testnet
+# Run a Validator on Public Testnet
 
 ::: tip
 Information on how to join the current testnet (`genesis.json` file and seeds) is held [in our `testnet` repo](https://github.com/cosmos/testnets/tree/master/latest). Please check there if you are looking to join our latest testnet.