modify title

README.rst

 RapidPeptidesGenerator (RPG)
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-Rapid Peptides Generator (RPG) is dedicated to predict cleavage sites of proteases.
+Rapid Peptides Generator (RPG) is dedicated to predict proteases-induced cleavage sites on amino acid sequences.
 
 .. image:: https://badge.fury.io/py/rpg.svg
     :target: https://badge.fury.io/py/rpg