build: improve project bootstrapping

Align autogen.sh with the one in NM:
  * Just calling autoreconf once
  * Using autopoint from GNU gettext
  * Enabling the use of NOCONFIGURE

.gitignore

@@ -49,10 +49,48 @@ po/POTFILES
 po/stamp-it
 po/.intltool-merge-cache
 po/ModemManager.pot
+po/Makevars.template
+po/Rules-quot
+po/boldquot.sed
+po/en@boldquot.header
+po/en@quot.header
+po/insert-header.sin
+po/quot.sed
+po/remove-potcdate.sin
 
 m4/gtk-doc.m4
 m4/intltool.m4
 m4/libtool.m4
 m4/lt*.m4
+m4/codeset.m4
+m4/gettext.m4
+m4/glibc2.m4
+m4/glibc21.m4
+m4/iconv.m4
+m4/intdiv0.m4
+m4/intl.m4
+m4/intldir.m4
+m4/intlmacosx.m4
+m4/intmax.m4
+m4/inttypes-pri.m4
+m4/inttypes_h.m4
+m4/lcmessage.m4
+m4/lib-ld.m4
+m4/lib-link.m4
+m4/lib-prefix.m4
+m4/lock.m4
+m4/longlong.m4
+m4/nls.m4
+m4/po.m4
+m4/printf-posix.m4
+m4/progtest.m4
+m4/size_max.m4
+m4/stdint_h.m4
+m4/uintmax_t.m4
+m4/visibility.m4
+m4/wchar_t.m4
+m4/wint_t.m4
+m4/xsize.m4
 
 TAGS
+ABOUT-NLS