title: Qt Creator faulty kits - can't remove them
body: <p>I have installed Qt Creator on Windows XP and it has several kits in it:</p>
  
  <pre><code>Desktop Qt 4.8.7 MSVC2008 32bit
  Desktop Qt 4.8.7 MSVC2010 32bit
  Desktop Qt 4.8.7 MSVC2010 64bit
  Desktop Qt 4.8.7 MinGW44 32bit(default)
  Desktop Qt 4.8.7 MinGW482 32bit
  Desktop Qt 5.4.2 MinGW 32bit2
  Desktop Qt 5.5.0 MinGW 32bit
  </code></pre>
  
  <p>The <code>MSVC</code> ones lack a compiler set, so they have a red annotation mark next to them. However, I only want to use the 4.8.7 MinGW ones, so I don't really need <code>MSVC</code>. However, even if I set <code>Desktop Qt 4.8.7 MinGW44 32bit</code> as default, when trying to build, I get an error <code>Qt Creator needs a compiler set up to build. Configure a compiler in the kit options.</code> The Remove button is greyed out, so I can't get rid of the faulty <code>MSVC</code> kits and I can't build while they're here. What can I do?</p>