Corrected xorriso docs about meaning of -jigdo-map and .md5 file addresses

xorriso/xorriso.1

@@ -2430,8 +2430,11 @@ listed in the .jigdo file and externally referenced in the .template file.
 Each desired file is represented in the .md5 file by a single text line:
 .br
 MD5 as 32 hex digits, 2 blanks, size as 12 decimal digits or blanks, 2 blanks,
-basename of file in the disk filesystem (directory path is allowed but gets
-ignored).
+file address
+.br
+The file address in an .md5 line has to bear the same basename as the
+absolute disk_path of the file which it shall match. The directory path of
+the file address is decisive for To=From mapping, not for file recognition.
 .br
 If the list of jigdo parameters is not empty, then xorriso will refuse to
 write to non-blank targets, it will disable multi-session emulation, and
@@ -2449,48 +2452,59 @@ No .jigdo and .template file will be produced.
 .br
 \fBtemplate_path\fR sets the disk_path for the .template file with the
 holed and compressed ISO image copy.
+.br
 Alias: -jigdo-template
 .br
 \fBjigdo_path\fR sets the disk_path for the .jigdo file with the checksums
 and download addresses for filling the holes in .template.
+.br
 Alias: -jigdo-jigdo
 .br
 \fBmd5_path\fR sets the disk_path where to find the .md5 input file.
+.br
 Alias: -md5-list
 .br
 \fBmin_size\fR sets the minimum size for a data file to be listed
 in the .jigdo file and being a hole in the .template file.
+.br
 Alias: -jigdo-min-file-size
 .br
 \fBexclude\fR adds a regular expression pattern which will get compared
 with the absolute disk_path of any data file. A match causes the file to
 stay in .template in any case.
+.br
 Alias: -jigdo-exclude
 .br
 \fBdemand_md5\fR adds a regular expression pattern which will get compared
 with the absolute disk_path of any data file that was not found in the .md5
 list. A match currently causes sudden program abort.
 (Should become a MISHAP event.)
+.br
 Alias: -jigdo-force-md5
 .br
 \fBmapping\fR adds a string pair of the form To=From to the parameter list.
-The absolute disk_path of any file that will be listed in the .jigdo file will
-be checked whether it begins with the From string. If so, this string will
-be replaced by the To string and a ':' character. The From string should end
-by a '/' character.
+If a data file gets listed in the .jigdo file, then it is referred by the
+file address from its line in the .md5 file. This file address gets checked
+whether it begins with the From string. If so, then this string will be
+replaced by the To string and a ':' character, before it goes into the .jigdo
+file. The From string should end by a '/' character.
+.br
 Alias: -jigdo-map
 .br
 \fBcompression\fR chooses one of "bzip2" or "gzip" for the compression of
 the template file. The jigdo file is put out uncompressed.
+.br
 Alias: -jigdo-template-compress
 .br
 \fBchecksum_iso\fR chooses one or more of "md5", "sha1", "sha256", "sha512"
 for the auxiliary "# Image Hex" checksums in the jigdo file. The value may e.g.
 look like "md5,sha1,sha512". Value "all" chooses all available algorithms.
 Note that MD5 stays always enabled.
+.br
 Alias: -checksum_algorithm_iso
 .br
 \fBchecksum_template\fR is like checksum_iso but for "# Template Hex".
+.br
 Alias: -checksum_algorithm_template
 .TP
 .B Character sets: