released 7.6

add new options --max-size and --min-size

implement #518 & #519 & #532

perform TTY and pipe check once

cleanup some loose ends

cleanup some loose ends

.* and .+ opt not .

remove superfluous ferror() branch in close_file()

-z threads fix for unlikely file read errors

#503 -Dread should block

fix #503 (redux)

fix #503

fix #503

Merge pull request #532 from outtersg/exclude-and-ignore-cross-doc

fix #518: relate ignore-files to exclude-from in the doc