tmLanguage plist indentation is wrong

[lilyball]

Property lists are XML files with standard indentation except by convention the sole child of the <plist> element is unindented. This looks like

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>foo</key>
  …
</dict>
</plist>

This extension is producing a file where this <dict> tag is indented.