[RFC] Qt5/KF5 based accounts-sso kaccount and ktp

there are several points which should be discussed before merging this:
* accounts-qt and libaccounts-glib: different name scheme, which name should be used?
* signond and signon-* packages: same as above
* some RDEPENDS might be missing
* Meta package missing
* ktp-call-ui missing (implies farstream missing, too)
* some llibraries don't have newest tarballs uploaded: accounts-qt, libaccounts-glib, signond
* optional/recommend features not handled well (adding USE flags for those where appropriate)