Update README.md

Author: Matt Turner

README.md

@@ -61,7 +61,9 @@ Possible values are ```legacy``` or ```stable``` or ```nightly```
 **If ```terminal``` is set to ```iTerm``` this setting is mandatory**
 
 ```"iTerm_version": "legacy",``` targeting iTerm 2.14
+
 ```"iTerm_version": "stable",``` targeting new versions of iTerm
+
 ```"iTerm_version": "nightly",```targeting only the nightly build of iTerm
 
 _This setting is ignored if your terminal is set to ```Terminal.app```_