better title/desc for homepage

_config.yml

@@ -1 +1,8 @@
 theme: jekyll-theme-cayman
+
+defaults:
+  - scope:
+      path: "README.md"
+      type: "pages"
+    values:
+      description: "Command-line chat tool for coding with GPT-4"

_layouts/default.html

@@ -20,7 +20,7 @@
     <header class="page-header" role="banner">
       {% if page.url == "/" %}
       <h1 class="project-name">aider</h1>
-      <h2 class="project-tagline">aider is GPT-4 powered coding in your terminal</h2>
+      <h2 class="project-tagline">GPT-4 powered coding in your terminal</h2>
       {% else %}
       <h1 class="project-name">{{ page.title | default: site.title | default: site.github.repository_name }}</h1>
       <h2 class="project-tagline">{{ page.description | default: site.description | default: site.github.project_tagline }}</h2>