Merged revisions 20790-20793 via svnmerge from 
svn+ssh://bugman@svn.gna.org/svn/relax/trunk

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  r20790 | bugman | 2013-09-04 10:37:19 +0200 (Wed, 04 Sep 2013) | 7 lines
  
  Defined two new functions called u() in the compat module for better unicode string support.
  
  The two functions are defined differently for Python2 and Python3.  The Python3 function simply
  returns the text unmodified, as all strings are unicode.  The Python2 function converts the str
  type to a unicode type.
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  r20791 | bugman | 2013-09-04 10:41:49 +0200 (Wed, 04 Sep 2013) | 3 lines
  
  Restored the Python3 aliased unicode() function accidentally removed in commit r20789.
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  r20792 | bugman | 2013-09-04 10:43:51 +0200 (Wed, 04 Sep 2013) | 3 lines
  
  The new compat.u() function is now being used for all unicode strings.
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  r20793 | bugman | 2013-09-04 10:52:10 +0200 (Wed, 04 Sep 2013) | 3 lines
  
  All "local tm" text in the GUI now uses a subscript m unicode character as well as the tau character.
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Unicode strings in the dispersion GUI elements is now set up with the compat.u() function.