bootstrap: Migrate linguas.sh into bootstrap.conf

Bootstrap has infrastructure for downloading/updating project po files
and generating the LINGUAS file. It uses wget instead of rsync, but
provides the same functionality, namely that only po files that have
a modification date before the corresponding one on the server will get
redownloaded. Bootstrap creates a pristine copy of the po files in
po/.reference, so update .gitignore to ignore that directory.

Bootstrap also creates the po/LINGUAS file, but it does not know to add
in GRUB's autogenerated po files. So move that code from linguas.sh into
the bootstrap epilogue.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

bootstrap.conf

@@ -63,8 +63,6 @@ checkout_only_file=
 copy=true
 vc_ignore=
 
-SKIP_PO=n
-
 # Build prerequisites
 buildreq="\
 autoconf   2.64
@@ -109,9 +107,23 @@ bootstrap_post_import_hook () {
 bootstrap_epilogue () {
   mv INSTALL.grub INSTALL
 
-  # Update translation files and create LINGUAS file used to determine
-  # the set of languages used to translate.
-  if [ "x$SKIP_PO" = "xn" ]; then
-    ./linguas.sh
+  if [ "x$SKIP_PO" = "x" ]; then
+    # Generate LINGUAS with all supported languages. Bootstrap will
+    # generate a LINGUAS, but it will not contain the autogenerated
+    # languages.
+    autogenerated="en@quot en@hebrew de@hebrew en@cyrillic en@greek en@arabic en@piglatin de_CH"
+
+    for x in $autogenerated; do
+      rm -f "po/$x.po";
+    done
+
+    (
+      (
+        cd po && ls *.po| cut -d. -f1
+        for x in $autogenerated; do
+            echo "$x";
+        done
+      ) | sort | uniq | xargs
+    ) >po/LINGUAS
   fi
 }