v1.7.0

Rollup of a lot of bugfixes and features that were pending.

• dropped: support for Red Hat Enterprise Linux and its derivatives has been dropped; removed the RPM spec file, and will no longer build binaries
• feature: the "--size" option now accepts "@filename" to use the size of another file (pull request #57 supplied by Dave Beckett)
• feature: the "--watchfd" option is now available on OS X (pull request #60 supplied by christoph-zededa)
• feature: new "--bits" option to show bit count instead of byte count (adapted from pull request #63 supplied by Nick Black)
• feature: new "--average-rate-window" option, to set the window over which the average rate is calculated, also used for ETA (modified from pull request #65 supplied by lemonsqueeze)
• feature: the "--watchfd" option will now show relative filenames, if they are under the current directory (pull request #66 supplied by ikasty)
• fix: correction to pv_in_foreground() to behave as its comment block says it should, when not on a terminal - corrects GH#19 "No output in Arch Linux initcpio after 1.6.6", GH#31 "No output written from inside zsh <() construct", GH#55 "pv Stopped Working in the Background" (pull request #64 supplied by Michael Weiß)
• fix: workaround for OS X 11 behaviour in configure script regarding stat64 at compile time (pull request #57 supplied by Dave Beckett)
• fix: workaround for macOS equivalence of stat to stat64 - patches from Filippo Valsorda and Demitri Muna, correcting GH#33 "Fix compilation problems due to stat64() on Apple Silicon"
• fix: add burst rate limit to transfer, so rate limits are not broken by bursty traffic (pull request #62 supplied by Volodymyr Bychkovyak)
• fix: corrected "--force" option so it will still output progress when not in the same process group as the owner of the terminal - corrects GH#23 "No output with "-f" when run in background after 1.6.6" and helps to correct GH#31 "No output written from inside zsh <() construct"
• fix: corrected elapsed time display to show as D:HH:MM:SS after 1 day, like the ETA does - corrects GH#16 "Show days in same format in ETA as in elapsed time"
• fix: corrected bug where percentages went down after 100% when in "--numeric" mode with a "--size" that was too small - corrects GH#26 "Correct "-n" behaviour when going past 100% of "-s" size"
• i18n: recoded Polish translation file to UTF-8
• i18n: removed inaccurate fuzzy translation matches
• docs: moved all open issues into GitHub and updated the TODO list
• docs: renamed README to README.md and altered it to Markdown format
• docs: moved contributors from the README to docs/ACKNOWLEDGEMENTS.md
• docs: moved TODO to TODO.md and altered it to Markdown format
• docs: moved NEWS to NEWS.md, converted it to UTF-8, and altered it to Markdown format