Bump version to 2.2.0 in README.

Author: lichray

README

@@ -1,4 +1,4 @@
-This is version 2.1.3 (2015-04-08) of nex/nvi, a reimplementation of the ex/vi
+This is version 2.2.0 (2020-08-01) of nex/nvi, a reimplementation of the ex/vi
 text editors originally distributed as part of the Fourth Berkeley
 Software Distribution (4BSD), by the University of California, Berkeley.
 
@@ -27,7 +27,7 @@ o Nvi was written by Keith Bostic, and the last version is 1.79.  After that,
 The following acknowledgments were written by Keith Bostic:
 
 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
-o This software is several years old and is the product of many folks' work.  
+o This software is several years old and is the product of many folks' work.
 
 	This software was originally derived from software contributed to
 	the University of California, Berkeley by Steve Kirkendall, the