updated for version 7.4.082
Problem:    Using "gf" in a changed buffer suggests adding "!", which is not
	    possible. (Tim Chase)
Solution:   Pass a flag to check_changed() wether adding ! make sense.
Added tag v7-4-082 for changeset 9c777e2c7024
Updated runtime files.
updated for version 7.4.083
Problem:    It's hard to avoid adding a used pattern to the search history.
Solution:   Add the ":keeppatterns" modifier. (Christian Brabandt)
Added tag v7-4-083 for changeset 6367a766027d