docs: polish

Author: cloydlau

README.md

@@ -26,7 +26,7 @@ JSON editor for Vue 2.6 / 2.7 / 3, powered by [svelte-jsoneditor](https://github
 
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-## Installation
+## Install
 
 ### Peer Dependencies
 
@@ -304,7 +304,7 @@ Detailed changes for each release are documented in the [release notes](https://
 
 <br>
 
-## Development
+## Develop
 
 **PR welcome!**