syntex.5 has many warnings from groff

[Mitsuya Shibata <mty.shibata@gmail.com>]

Dear TeX Live maintainers,

web2c/synctexdir/man5/synctex.5 has many warnings from groff.
$ man --warning -l web2c/synctexdir/man5/synctex.5 > /dev/null
mdoc warning: Using a macro as first argument cancels effect of .Li (#61)
mdoc warning: A .Bl directive has no matching .El (#272)
mdoc warning: Unknown keyword `-offset' (or missing display type)
              in .Bd macro (#277)
<standard input>:277: warning: macro `display-type-stack1' not defined
mdoc warning: Empty input line #311

(reduced duplication)

In attached patch, use to following resolutions.

.Li's warning is about ".Li Qq foo" lines. First ".Li" means
"this line is literal text", second is "do quote foo".
I changed they lines to ".Qq foo", then got same result
without warning.

.Bl/.El waring means "not ended list structure".
I added .El to appropriate place.

.Bd warning means "not specify display typei for display block".
I added "-literal" option.

Empty input line is line which is just only ".".
I removed it.

Best regards,
-- 
Mitsuya Shibata
mty.shibata@gmail.com

Index: web2c/synctexdir/man5/synctex.5
===================================================================
--- web2c/synctexdir/man5/synctex.5	(リビジョン 25572)
+++ web2c/synctexdir/man5/synctex.5	(作業コピー)
@@ -58,21 +58,21 @@
 .Li <Preamble> ::=
 .Bl -item -offset indent
 .It
-.Li Qq SyncTeX Version:
+.Qq SyncTeX Version:
 <Version Number> <EOL>
 .It
 .Li <Input Line>*
 .It
-.Li Qq Magnification:
+.Qq Magnification:
 <TeX magnification> <EOL>
 .It
-.Li Qq Unit:
+.Qq Unit:
 <unit in scaled point> <EOL>
 .It
-.Li Qq X Offset:
+.Qq X Offset:
 <horizontal offset in scaled point> <EOL>
 .It
-.Li Qq Y Offset:
+.Qq Y Offset:
 <vertical offset in scaled point> <EOL>
 .El
 .It
@@ -91,7 +91,7 @@
 .It
 .Li <byte offset record>
 .It
-.Li Qq Content:
+.Qq Content:
 <EOL>
 .It
 .Li <sheet(1)>
@@ -122,14 +122,14 @@
 .It
 .Li <byte offset record>
 .It
-.Li Qq \&{
+.Qq \&{
 <the integer n> <end of record>/
 .It
 .Li <box content>*
 .It
 .Li <byte offset record>
 .It
-.Li Qq \&}
+.Qq \&}
 <the integer n> <end of record>
 .El
 .El
@@ -152,7 +152,7 @@
 .Li <vbox section> ::=
 .Bl -item -offset indent
 .It
-.Li Qq \&[
+.Qq \&[
 <link>
 .Qq \&:
 <point>
@@ -161,14 +161,14 @@
 .It
 .Li <box content>*
 .It
-.Li Qq \&]
+.Qq \&]
 <end of record>
 .El
 .It
 .Li <hbox section> ::=
 .Bl -item -offset indent
 .It
-.Li Qq \&(
+.Qq \&(
 <link>
 .Qq \&:
 <point>
@@ -177,7 +177,7 @@
 .It
 .Li <box content>*
 .It
-.Li Qq \&)
+.Qq \&)
 <end of record>
 .El
 .El
@@ -266,15 +266,16 @@
 .It
 .Li <byte offset record>
 .It
-.Li Qq Count:
+.Qq Count:
 <Number fo records> <EOL>
 .El
+.El
 .Sh The post scriptum
 The post scriptum contains material possibly added by 3rd parties.
 It allows to append some transformation (shift and magnify).
 Typically, one applies a dvi to pdf filter with offset options and magnification,
 then he appends the same options to the synctex file, for example
-.Bd -offset indent
+.Bd -literal -offset indent
 	synctex update -o foo.pdf -m 0.486 -x 9472573sp -y 13.3dd source.dvi
 .Ed
 .Bl -item -offset indent
@@ -286,25 +287,25 @@
 .It
 .Li <byte offset record>
 .It
-.Li Qq Post Scriptum:
+.Qq Post Scriptum:
 <EOL>
 .It
-.Li Qq Magnification:
+.Qq Magnification:
 <number> <EOL>
 .Pq Set additional magnification
 .It
-.Li Qq X Offset:
+.Qq X Offset:
 <dimension> <EOL>
 .Pq Set horizontal offset
 .It
-.Li Qq Y Offset:
+.Qq Y Offset:
 <dimension> <EOL>
 .Pq Set vertical offset
 .El
+.El
 This second information will override the offset and magnification previously available in the preamble section.
 All the numbers are encoded using the decimal representation with "C" locale.
 .Sh USAGE
 .Pp
 The <current record> is used to compute the visible size of hbox's.
 The byte offset is an implicit anchor to navigate the synctex file from sheet to sheet.
-.