chore: update options in readme

Author: Justineo

README.md

@@ -60,10 +60,22 @@ For browser extension versions, GitHub Hovercard provide following options:
 
  Use this option to set custom domains for your GitHub Enterprise service. Note that you don't need to set `github.com` because it's always included. You may be asked to grant additional permissions for those domains.
 
+* Theme
+
+ The theme of hovercards. Defaults to GitHub-style hovercards. You can set it back to the classic dark style in the options.
+
 * Delay
 
  If you don't want the hovercards to pop up instantly, you may set a delay before they try to retrieve data and appear.
 
+* Disable Projects
+
+ You can disable hovercards on project pages for less interference.
+
+* Placement
+
+ You can set the default placement of the hovercards.
+
 * Readme
 
  You may disable readme content for repo cards if you don't need it.