This is mostly a simple lexical search+replace but the absence of operator< for
std::weak_ptr<T> leads to some complications, particularly with Evoral::Sequence
and ExportPortChannel.
This follows 5a41ca8fdf and df1e6fda2d.
Even though this kind of precision is rarely needed, rounding
to a single digit is inconsistent with various places that display
more than one digit, or allow more accurate control.
