Uses langdefs.py to create language list for create-weblinks-itexi.py (issue 4951047)

[PhilEHolmes]

Reviewers: Graham Percival,

Message:
As requested - please review.

Description:
This demonstrates how to import a library into a python file where the
path is not already in the pathlist.  It half-fixes the issue where
languages are defined in many places in make website - the other needs
changes to website.make, but there is a problem with that since the
variable PYTHON is not guaranteed to be defined.

Please review this at http://codereview.appspot.com/4951047/

Affected files:
  M scripts/build/create-weblinks-itexi.py


Index: scripts/build/create-weblinks-itexi.py
diff --git a/scripts/build/create-weblinks-itexi.py  
b/scripts/build/create-weblinks-itexi.py
index  
d799925909c9c4933527cafe77bfb56149977c4b..1f4d90f21fcacb5427be8fe1d5384d679e995e75  
100644
--- a/scripts/build/create-weblinks-itexi.py
+++ b/scripts/build/create-weblinks-itexi.py
@@ -9,14 +9,40 @@ import sys
 import os
 import glob

-# these links are relative from /website/ on lilypond.org
-depth = "../"
-
 ### translation data -- shouldn't be here; see issue
 ### http://code.google.com/p/lilypond/issues/detail?id=1050

-#langs = ['', 'cs', 'de', 'es', 'fr', 'hu', 'it', 'ja', 'nl', 'zh']
-langs = ['', 'cs', 'de', 'es', 'fr', 'hu', 'it', 'ja', 'nl', 'zh']
+LangDefsImported=True
+langs = []
+
+try:
+    import langdefs
+except:
+    LangDefsImported=False
+
+if not LangDefsImported:
+    LangDefsImported=True
+    try:
+        SrcDir = sys.argv[1]
+        ScriptDir = os.path.join(SrcDir, 'python')
+        sys.path.insert(0, ScriptDir)
+        import langdefs
+    except:
+        # Unable to find langdefs
+        LangDefsImported=False
+        langs = ['', 'cs', 'de', 'es', 'fr', 'hu', 'it', 'ja', 'nl', 'zh']
+        sys.stderr.write ('create-weblinks-itexi: warning: unable to find  
langdefs: language list may be wrong')
+
+if LangDefsImported:
+    langobjs = langdefs.LANGUAGES
+    for i in langobjs:
+        if i.code == 'en':
+            langs.append ('')
+        else:
+            langs.append(i.code)
+
+# these links are relative from /website/ on lilypond.org
+depth = "../"

 # Get/update node translations
 '''