add kdav to KDE/Applications 17.04

[Sandro Knauß]

Hey,

kdav is now splitted out of kdepim-runtime and kdepim-runtime depends now on 
kdav on master; boths builds successfully on CI.

Please add kdav to the upcomming release of KDE/Applications 17.04.

Dependencies:
KF5::CoreAddons
KF5::KIO
Qt::Core
Qt::Gui
Qt::XmlPatterns
Qt::Test

@montel: can you add kdav to the normal scripts that bump the versions for 
beta,rc etc.?

Best Regards,

sandro