move fingerprint coloring into helper
certify: add certify action button to viewkeymainfragment
certify: selectsecretkeyfragment cosmetics
certify: viewkeyuseridsadapter cosmetics and checkbox capability
certify: support PUBLIC_KEY_RING_BY_MASTER_KEY_ID_USER_ID uri (haha)
certify: revamp certifykeyactivity

show info on the key to be certified, along with a list of (selectable)
user ids. user ids are handed through to the signing service, but not
yet handled.
certify: add some subscopes in PgpKeyOperation for readability

note this commit introduces NO semantical changes whatsoever!
certify: sign individual UIDs

direct signing of pubkeys is out for now. not sure how this should be
handled, but it's trivial to re-add so leaving this up for discussion
for now.
certify: preserve user id certificates when saving secret keys
Merge pull request #430 from Valodim/certify

Revamp certify dialogue