s/compiler/library in index

index.txt

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 Theano
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-An optimizing compiler for matrix valued expressions in Python
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+-------------------------------------------------------------------
+A python library for manipulating and evaluating matrix expressions
+-------------------------------------------------------------------
 
-Theano is an optimizing compiler in Python, built to evaluate complicated
+Theano is a library in Python, built to evaluate complicated
 expressions (especially matrix-valued ones) as quickly as possible.
 It was written at LISA_ to explore techniques for machine learning.
 Our project uses the name to honour the ancient Greek mathematician.