Right now, the Gaudi::Property<T> code assumes that the type T is
default-constructible. But it only uses this assumption when a value of
type T is parsed from a string. With a couple of modifications to the
string parsing function, Gaudi::Property<T> can work with
copy-constructible types as well.

See merge request gaudi/Gaudi!582

Added a new event loop manager for HLT like usage, that is very simple and very fast scheduling (mr !537)

Closes #1

Fixed use of zlib

See merge request gaudi/Gaudi!553