Update net-im/libqmatrixclient and net-im/quaternion in tandem.
New release of libqmatrixclient (which breaks API compatibility) and
a beta for quaternion (its only client).
- (packaging) QtMultimedia (video support) and QtKeychain (for secure storage) are now added as dependencies.
- (user-visible) Many UI improvements.
This could use some work on the BUILD_DEPENDS to make sure that quaternion
is upgraded together with the static library it depends on.