Preconfigured toolchains in Creator should have distinctive names instead of indices

1. Install the Qt version, Qt Creator and MinGW from a Qt package.
2. Start Creator with empty settings, e.g. by using the command line parameter -settingspath.
3. Go to "Tools" -> "Options..." -> "Build & Run" -> "Kits".
4. Select the preconfigured kit which uses MinGW.
   Two compilers are configured for this kit:

   C	MinGW <version> 32bit
   C++	MinGW <version> 32bit2

Instead, the names should represent which compiler is for what, e.g.: