man: fill out fi_tsearch flags and errors

List FI_CLAIM as a flag that is applicable to fi_tsearch.
The section was marked with a "write me" before.

-FI_EINVAL and -FI_EOTHER - two other errors that can be
returned.
Merge pull request #12 from sayantansur/man-tagged

man: fill out fi_tsearch flags
Merge remote branch 'upstream/master'