Create list of translation in po4a.conf

Instead of requiring the script file to contain the list of
translations, just extract it from the list of po files on the
filesystem.

Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>

Makefile

@@ -15,8 +15,8 @@ ifndef V
 endif
 endif
 
-po4a.conf: scripts/create_po4a_conf.sh sources.txt
-	./scripts/create_po4a_conf.sh
+po4a.conf: scripts/create_po4a_conf.sh sources.txt $(LANGUAGE_PO)
+	@./scripts/create_po4a_conf.sh
 
 po4a-stamp: po4a.conf $(EN_SOURCES) $(LANGUAGE_PO) Makefile
 	$(QUIET_PO4A)PERL5LIB=./po4a/lib po4a/po4a -v po4a.conf

README

@@ -97,15 +97,15 @@ Initializing a documentation.XX.po file
 If your language XX does not have translated message file
 documentation.XX.po yet, you add a translation for the first time by
 
- * editing the file create_po4a_conf.sh and adding your language code
-   to the first line, e.g. "[po4a_langs] fr XX", where XX is the
-   locale, such as "de", "is", "pt_BR", "zh_CN", etc.
- * running in the root directory of the project
-
-     make all
+ * initializing the translation po file by running:
+       msginit --local=XX
+   in the po/directory, where XX is the locale, e.g. "de", "is", "pt_BR",
+   "zh_CN", etc.
+ * pre-translating the file for unchanged strings by running:
+       scripts/pre-translate-po po/documentation.XX.po
 
 A file po/documentation.XX.po was created, corresponding
-to the newly created translation.
+to the newly created translation and is ready for your translations.
 
 Then edit the automatically generated copyright info in your new
 documentation.XX.po to be correct, e.g. for Icelandic:
@@ -126,8 +126,7 @@ just "Git Documentation":
     Documentation/' documentation.XX.po
 
 Once you are done testing the translation (see below), commit the
-create_po4a_conf.sh and documentation.XX.po files and ask the l10n coordinator
-to pull from you.
+documentation.XX.po files and ask the l10n coordinator to pull from you.
 
 Updating a documentation.XX.po file
 -----------------------------------
@@ -140,7 +139,7 @@ file.
 
 If there's an existing documentation.XX.po file for your language, but
 the repository of the l10n coordinator has newer documentation.pot
-file, chances are the new documentation.XX.po already includes the
+file, chances are the upstreamed documentation.XX.po already includes the
 changes of the new version.
 
 Once you are done testing the translation (see below), commit the result

scripts/create_po4a_conf.sh

 #!/bin/bash
 
-cat <<EOF >po4a.conf
-[po4a_langs] fr de
+echo -n "[po4a_langs]" >po4a.conf
+for l in po/documentation.*.po
+do
+    rstripped=${l%%.po}
+    echo -n " ${rstripped##po/documentation.}" >> po4a.conf
+done
+echo >> po4a.conf
+
+cat <<EOF >>po4a.conf
 [po4a_paths] po/documentation.pot \$lang:po/documentation.\$lang.po
 [options] opt: " -k 80"