Simplify cmake3 integration

CentOS7 only provides "cmake" versions 2.x.x by default. A common way to install newer cmake is to install cmake3.

However, when I select it in "Tools -> Options -> Build & Run -> CMake" it get a broken configuration, with a warning:

Warning: CMake version is unsupported. Please update to version 3.0

It looks like Qt Creator cmakeprojectmanager plugin seem to work via

QRegularExpression versionLine("^cmake version ((\\d+).(\\d+).(\\d+).*)$");}}

However, i get a slightly different output:

[user@host folder]$ cmake3 --version
cmake3 version 3.6.3

Personally (after running into this), I ended up using the following wrapper as a workaround:

#!/bin/bash
if [ $# -eq 1 ] && [ "--version" = $1 ]; then
    echo === for Qt: =======
    echo cmake version 3.6.3
    echo ===================
fi

cmake3 "$@"
exit 0

It works (at least, I was able to build my project OK), but it would be nice if cmake3 would be natively supported. Maybe, it would be enough to modify that QRegularExpression, so that it would match "cmake3" as well?