Fix line ends mismatches in testsuite
Fix line ends mismatches in testsuite

Note the issue is not triggered on AppVeyor, but it is triggered when
checking files out on Windows using recommended Git settings (Windows
newlines).

Workaround for
https://github.com/nikita-volkov/neat-interpolation/issues/14, no more
necessary if that bug is fixed.

This defines a variant of shouldBe; while at it, also integrate needed
string type conversions.

MichielDerhaeg/stack,juhp/stack,AndreasPK/stack,Blaisorblade/stack,Blaisorblade/stack,anton-dessiatov/stack,MichielDerhaeg/stack,Fuuzetsu/stack,anton-dessiatov/stack,AndrewRademacher/stack,mrkkrp/stack,deech/stack,AndreasPK/stack,deech/stack,Fuuzetsu/stack,martin-kolinek/stack,AndrewRademacher/stack,juhp/stack,martin-kolinek/stack,mrkkrp/stack