unify xo::parameter handling with classical parameter handling (parameter::get). This change implements calls for "::xo::parameter get" by parameter::get and outputs deprecated log entries. In addition, the initialization of all parameters is deactivated, such that startup time is slightly faster.
so far, the full code is kept but deactivated to allow to change quickly back, in case early adaptors run into troubles.
At least in cases, where new naviserver versions are used, the implementaton of parameter::get became sufficiently fast to beat the xo::parameter implementation, which was at time of its introduction ~30x faster.