typo in .tex and replacement of obsolete OS reference

doc/Guidebook.mn

@@ -35,7 +35,7 @@
 .ds vr "NetHack 3.7
 .ds f0 "\*(vr
 .ds f1
-.ds f2 "February 15, 2020
+.ds f2 "February 17, 2020
 .
 .\" A note on some special characters:
 .\" \(lq = left double quote
@@ -1580,7 +1580,7 @@ with another key, modifies it by setting the \(lqmeta\(rq [8th,
 or \(lqhigh\(rq] bit), you can invoke many extended commands by meta-ing
 the first letter of the command.
 .pg
-In \fINT\fP, \fIOS/2\fP, \fIPC\fP and \fIST\fP \fINetHack\fP,
+In \fIWindows\fP, \fIOS/2\fP, \fIPC\fP and \fIST\fP \fINetHack\fP,
 the \(lqAlt\(rq key can be used in this fashion;
 on the \fIAmiga\fP, set the
 .op altmeta

doc/Guidebook.tex

@@ -45,7 +45,7 @@
 %.au
 \author{Original version - Eric S. Raymond\\
 (Edited and expanded for 3.7 by Mike Stephenson and others)}
-\date{February 15, 2020}
+\date{February 17, 2020}
 
 \maketitle
 
@@ -1680,7 +1680,7 @@ Help menu:  get the list of available extended commands.
 with another key, modifies it by setting the `meta' [8th, or `high']
 bit), you can invoke many extended commands by meta-ing the first
 letter of the command.
-In {\it NT, OS/2, PC\/ {\rm and} ST NetHack},
+In {\it Windows, OS/2, PC\/ {\rm and} ST NetHack},
 the `Alt' key can be used in this fashion;
 on the {\it Amiga}, set the {\it altmeta\/} option to get this behavior.
 On other systems, if typing `Alt' plus another key transmits a
@@ -5647,7 +5647,7 @@ Valid choices are ``{\tt historical}'' for binary writing of entire structs,
 ``{\tt ascii}'' for writing the bones file content in ascii text.
 %.lp
 \item[\ib{SUPPORT}]
-A string explainign how to get local support (no default value).
+A string explaining how to get local support (no default value).
 %.lp
 \item[\ib{RECOVER}]
 A string explaining how to recover a game on this system (no default value).