Quiet curl in the install command for clearer output

Without this, when a sudo password is required, the password prompt is confusingly obscured by the curl output. Adding -s hides that initial output making this much clearer.

README.md

@@ -24,12 +24,12 @@ This is just one tool in the chain. `notes` is a command line tool, and some peo
 ### Automatic:
 
 ```bash
-curl -L https://raw.githubusercontent.com/pimterry/notes/latest-release/install.sh | sudo bash
+curl -Ls https://raw.githubusercontent.com/pimterry/notes/latest-release/install.sh | sudo bash
 ```
 This will install `notes`, a default configuration, a man page, and bash completion if possible.
 
 ```bash
-curl -L https://raw.githubusercontent.com/pimterry/notes/latest-release/install.sh | PREFIX=$HOME bash
+curl -Ls https://raw.githubusercontent.com/pimterry/notes/latest-release/install.sh | PREFIX=$HOME bash
 ```
 For non-root installation(user directory).