IPMatcher: Remove NetworkReality

IPMatcher's interface currently consists of a couple of static methods
that partly depend on the non-static class NetworkReality to enable mocking of DNS lookups.

This patch removes NetworkReality together with the static hostname glob matching method in
IPMatcher that used it.

This patch also renames a method from convertToIPv4IfPossible to
tryConvertToIPv4.

Acked-by: Tigran
Target: master
Require-book: no
Require-notes: no