Rewrite script with numpy features

Use the possibility to sum, slice, apply cos, sin
on Numpy array.
Push the parser into a function.
Add the possibility to plot the ellipse.
Add comments and docstrings.
Rewrite function readSimulationParameters

Add header info to the file.
Add docstring to the function.
Change the method to open a file.
Rewrite function readVelocityData()

Change the way to open the file.
Change range by xrange.
Delete unecessary libraries.
Add docstring to the function.
Rewrite functions in a numpy/pythonic way

The name of the functions should be changed
to match PEP8. Will be done later to not break
the other depedencies.

Add docstring and comments.
Rewrite code in a more pythonic way

Use numpy capabilities.
Add docstrings to funtions.
Add argument '--show' and function to plot
the initial configuration and the rotated one.
Rewrite code in a more pythonic way

Add docstrings and comments.
Push parser inside function read_inputs.
Remove useless imports.

It seems that the variable `i_start`, `i_end`, `j_start` and `j_end`
are useless in this code.

I do not understand the flag `--plot-only`. What else do you want to do?

The parser argument `--vortlim` seems useless here.
Rewrite code in a more pythonic way

Add docstring and comments.
Push parser inside a function.
WIP: find a new way to calculate the vorticity with numpy.
Rewrite the script to plot the vorticity

Push parser into a function.
Add docstrings and comments.
Rewrite script to analyse the vorticity

Push parser into a function.
Add docstrings and comments.
Use Numpy utilities such as sum.
Add argument `--show` to parser to plot the figure
in an interactive mode.
Change output file name and location

The output generated by the script is now named
'total_vorticity.png' instead of 'out.png'
and is saved in the folder of the simulation case
instead of the current directory.

Delete the while loop to compute the number of saved points.
Now, calculate using `int()`.
Rewrite script with Numpy and comments

Add header to describe the script.
Push parser into a function.
Add argument `--show` to parser to plot the figure.
Use Numpy features to compute arrays.
Write into file using Numpy function savetxt.
Rewrite script with comments and Numpy features

Push parser into a function.
Add argument `--show` to parser to display the figure.
Create function `plot_body` to plot the body.
Use Numpy features to load coordinates, and get the properties
of the given body.
Edit python scripts.

* Add Olivier as an author.
* Add options u_lim and v_lim for plotVelocity.py.
* Add more files/folders to .gitignore.
* Change variable temp to previous_mean.
* Remove unnecessary options from plotVelocity.py.
* Make plotVelocity.py work without X.
Rename files using American spelling.
Edit Python scripts.

* Remove extraneous lines.
* Start all vorticity plot files names with vort.
* Make default infile in rotateBody.py same as output of naca00xx.py.
* Edit .gitignore.
Merge pull request #10 from barbagroup/python_script

Re-write some of the Python scripts