[PATCH 1/6] common: Disable enum type stream operators for Qt >= 5.14

[PATCH 1/6] common: Disable enum type stream operators for Qt >= 5.14

From 579e559a6322209df7cd51c34801fecff5fe734b Mon Sep 17 00:00:00 2001
Bug: https://bugs.quassel-irc.org/issues/1544
Bug-Ubuntu: https://bugs.launchpad.net/quassel/+bug/1885436
Origin: upstream, https://github.com/quassel/quassel/pull/518
Origin: upstream, https://github.com/quassel/quassel/commit/579e559a6322209df7cd51c34801fecff5fe734b

Starting from version 5.14, Qt provides stream operators for enum
types, which collide with the ones we ship in types.h. Disable
Quassel's stream operators when compiling against Qt 5.14 or later.

Add a unit test that ensures that enum serialization honors the width
of the underlying type.

Gbp-Pq: Topic qt514
Gbp-Pq: Name 0001-common-Disable-enum-type-stream-operators-for-Qt-5.1.patch