Separation from lrzip

[pete4abw]

At long last, there are no more file overlaps with lrzip and lrzip-next. All common files and man pages have been made unique in lrzip-next. All convenience symlinks, man pages, and programs are prefixed with lrzn consistently.

This was suggested by someone. I would like to attribute this enhancement, so let me know who you are!

Old Name	New Name
lrz	lrzn
lrz.1	lrzn.1
lrzcat	lrzncat
lrzcat.1	lrzncat.1
lrztar	lrzntar
lrztar.1	lrzntar.1
lrzuntar	lrznuntar
lrzuntar.1	lrznuntar.1
lrunzip	lrznunzip
lrunzip.1	lrznunzip.1

Currently these changes are staged in the whats-next branch for review and test. Tagged as v0.8.11

[demhademha]

Suggested in #66 (comment)

[pete4abw]

I was trying to find that! Thank you for the push.