This reverts commit b90704e4.

The host was renamed, somehow that was not executed on the host so the
configure script was confused

The version of EPICS (3 or 7) is now defined by which EPICS version is
used by the found adapter. There are no distinct names any more, also
EPCIS3 is effectively phasing out.

We are only polling those variables

This warning is frequently hit when using e.g. the ReadAnyGroup in
ApplicationCore, but we fail to see any benefit coming from this warning
for other scenarious. Hence we decided to disable it. Object slicing
is valid C++ and the behaviour is rather obvious.

Used in XFEL

Limit scans to SASE

Accidentally removed by removing type conversions