descpage: Implement inserting helptext in code

Add helping comments to beginning of gnuplot scripts explaining data
source

Issue #1 (#1)

euroexchange/descpage.py

@@ -23,6 +23,7 @@
 #
 
 import os
+import re
 
 import pywikibot
 import mwparserfromhell as mwparser
@@ -85,6 +86,13 @@ class DescPageBot(pywikibot.bot.Bot):
             replace( "system(\"echo $OUTFILE\")",
                       "'{}'".format (os.path.basename( self.job.image ) ) )
 
+        # Locate first empty line
+        m = re.search(r"^\s*$", gnuplot_script, re.MULTILINE)
+        if m:
+            # Insert help lines
+            gnuplot_script = gnuplot_script[:m.end()] +\
+                Config.gnuplot_script_help + gnuplot_script[m.end():]
+
         return gnuplot_script
 
     def parse_page(self):