Adjust .gitignore

To preserve the content/_index.md page.

.gitignore

@@ -14,7 +14,7 @@
 # Dependency directories (remove the comment below to include it)
 # vendor/
 cmd/hugothemesitebuilder/hugothemesitebuilder
-cmd/hugothemesitebuilder/build/site/content
+cmd/hugothemesitebuilder/build/site/content/themes
 cmd/hugothemesitebuilder/build/site/public
 cmd/hugothemesitebuilder/build/.vscode/settings.json
 .hugo_build.lock

cmd/hugothemesitebuilder/build/site/content/_index.md

@@ -0,0 +1,5 @@
+---
+title: "Complete List"
+linkTitle: "Home"
+date: 2017-07-25T09:00:00-05:00
+---