Regenerate README from man page

Closes #97

README

@@ -6,7 +6,7 @@ NAME
        z - jump around
 
 SYNOPSIS
-       z [-chlrt] [regex1 regex2 ... regexn]
+       z [-chlrtx] [regex1 regex2 ... regexn]
 
 AVAILABILITY
        bash, zsh
@@ -28,6 +28,8 @@ OPTIONS
 
        -t     match by recent access only
 
+       -x     remove the current directory from the datafile
+
 EXAMPLES
        z foo         cd to most frecent dir matching foo