Corrected example.py so that it also works with Python 2.

Clarified the README to highlight that the cmsisdsp Python package
is installed in editable mode when using the command line of the README
file.

PythonWrapper/README.md

@@ -44,7 +44,7 @@ Install some packages
     > pip instal scipy
     > pip instal matplotplib
 
-Now, you can install the cmsisdsp package:
+Now, you can install the cmsisdsp package in editable mode:
 
    > pip install -e "Path To The Folder Containing setup.py"
 

PythonWrapper/example.py

@@ -70,7 +70,7 @@ nbSamples=sigQ31.shape[0]
 # Here we demonstrate how we can process a long sequence of samples per block
 # and thus check that the state of the biquad is well updated and preserved
 # between the calls.
-half = round(nbSamples / 2)
+half = int(round(nbSamples / 2))
 res2a=dsp.arm_biquad_cascade_df1_q31(biquadQ31,sigQ31[1:half])
 res2b=dsp.arm_biquad_cascade_df1_q31(biquadQ31,sigQ31[half+1:nbSamples])
 res2=Q31toF32(np.hstack((res2a,res2b)))