fix gaussFilter's wrong ppm width

[cbielow]

Description

ppm computation for the gaussian width was off by 1 order of magnitude
(using 10e-6 is not 10^-6 :) )

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• Updated or added python bindings for changed or new classes (Tick if no updates were necessary.)

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[timosachsenberg]

sounds a bit rude ;)

checking (template <typename ConstIterT, typename IterT> bool filter(ConstIterT mz_in_start, ConstIterT mz_in_end, ConstIterT int_in_start, IterT mz_out, IterT int_out)) ... 
 -  line 91:TEST_REAL_SIMILAR(in,1.0): argument in does not have a floating point type!  Go fix your code!
 -  line 91:TEST_REAL_SIMILAR(in,1.0): argument in does not have a floating point type!  Go fix your code!
 -  line 91:TEST_REAL_SIMILAR(in,1.0): argument in does not have a floating point type!  Go fix your code!
 -  line 91:TEST_REAL_SIMILAR(in,1.0): argument in does not have a floating point type!  Go fix your code!
 -  line 91:TEST_REAL_SIMILAR(in,1.0): argument in does not have a floating point type!  Go fix your code!
: failed