adjust relevance of kcms in service runner

kcms are handy but not nearly as handy as an actual application. this is
particular notable with the test case where the user could type 'virt'
but that wouldn't have pushed virtualization software to the top but kcms
since kcms are kde things so they always get a .09 bump to
relevance.

the revised scoring excludes kcms from the bump and further reduces the
relvance by the tiniest fraction. this results in all applications that
match at least as well as the KCM to outscore the KCM