Use QString::splitRef in customtype example

There is no need to allocate all these strings

Change-Id: I398e1cc05bd3ad24df067a967a5e24fbc6d452ce
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Optimize qdatetime string parsing

Replacing usage QString::split by QString::splitRef saves a few
allocations.

Change-Id: I1cadca296279248b75af6f9f8394c54f13c37c55
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Bump version to 5.5

Change-Id: I8fd9ec2ea1138a94478b73a284ea1b550b62bd5a
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>