Update man pages to clarify upper/lower case for set/get commands

doc/man1/rigctl.1

@@ -351,12 +351,12 @@ Since most of the
 .B Hamlib
 operations have a
 .BR set " and a " get
-method, an upper case letter will often be used for a
+method, a single upper case letter will often be used for a
 .B set
-method whereas the corresponding lower case letter refers to the
+method whereas the corresponding single lower case letter refers to the
 .B get
 method.  Each operation also has a long name; in interactive mode, prepend a
-backslash, \(oq\\\(cq, to enter a long command name.
+backslash, \(oq\\\(cq, to enter a long command name all lower case.
 .
 .PP
 Example: Use \(lq\\dump_caps\(rq to see what capabilities this radio and

doc/man1/rigctld.1

@@ -414,12 +414,12 @@ Since most of the
 .B Hamlib
 operations have a
 .BR set " and a " get
-method, an upper case letter will be used for
+method, a single pper case letter will be used for
 .B set
-methods whereas the corresponding lower case letter refers to the
+methods whereas the corresponding single lower case letter refers to the
 .B get
 method.  Each operation also has a long name; prepend a backslash, \(oq\\\(cq,
-to send a long command name.
+to send a long command name all in lower case.
 .
 .PP
 Example (Perl): \(lqprint $socket "\\\\dump_caps\\n";\(rq to see what the