Compress the manpage

Signed-off-by: Alexey Neyman <stilor@att.net>

Makefile.am

@@ -19,6 +19,9 @@ man1_MANS	= docs/ct-ng.1
 # paths.sh generated by configure
 nobase_dist_pkgdata_DATA = $(verbatim_data) paths.sh
 
+# ct-ng, as renamed by the installation
+ctng_progname		= `echo ct-ng | sed '$(transform)'`
+
 USER_MANUAL_FILES = \
 	docs/manual/1_Introduction.md \
 	docs/manual/2_Installation.md \
@@ -44,7 +47,7 @@ do_subst		= ( @SED@ \
 			-e 's,[@]docdir[@],$(docdir),g' \
 			-e 's,[@]pkgdatadir[@],$(pkgdatadir),g' \
 			-e 's,[@]pkglibexecdir[@],$(pkglibexecdir),g' \
-			-e 's,[@]progname[@],'`echo ct-ng | sed '$(transform)'`',g' \
+			-e 's,[@]progname[@],'$(ctng_progname)',g' \
 		| $(SHELL) config.status --file=- )
 
 ct-ng: ct-ng.in Makefile
@@ -56,5 +59,12 @@ docs/ct-ng.1: docs/ct-ng.1.in Makefile
 bash-completion/ct-ng: bash-completion/ct-ng.in Makefile
 	$(AM_V_GEN)$(MKDIR_P) bash-completion && $(do_subst) < $< >$@-t && mv -f $@-t $@
 
+# automake doesn't offer an option to compress manpages, do it after installation
+install-data-hook:
+	gzip -9 $(DESTDIR)$(man1dir)/$(ctng_progname).1
+
+uninstall-hook:
+	rm -f $(DESTDIR)$(man1dir)/$(ctng_progname).1.gz
+
 dist-hook: maintainer/download-docs.sh
 	$< $(top_distdir) $(USER_MANUAL_FILES)