[Lesson 01] Add blank spaces and semicolons.

Add blank spaces to make the code more readable,
and add a semicolon at the end of the last plotting instructions
to suppress the display of the output.
[Lesson 01] Remove semicolon on first plot and add explanation about it.

I removed the semicolon on the first plot, to show that IPython
is displaying info about the object's instance.
I added an short explanation about the semicolon, right after the second plot.
Add a blank space.
[Lesson 01] Add a blank space.
[Lesson 02] Add blank spaces to make the code more readable.
[Lesson 02] Change function names

Now, function names have lowercases and
words are separated by underscores.
[Lesson 03] Add blank spaces, underscores, and remove blackslahes.

Add blank spaces to make the code more readable.
Add underscores in function names (lowercases).
Remove unecessary blackslahes when having parentheses.
Use implicit continuation inside parentheses to continue statements.
[Lesson 04] Add blank spaces, underscores, remove backslashes.

Add blank spaces to make the code more readable.
Add underscores in lowercases function names.
Use implicit parentheses to continue statements,
instead of backslashes.
[Lesson 06] Add blank spaces, underscores, remove backslashes.

Add blank spaces to make the code more readable.
Add underscores in lowercases function names.
Use implicit parentheses to continue statements,
instead of backslashes.
[Lesson 07] Add blank spaces, underscores, remove backslashes.

Add blank spaces to make the code more readable.
Add underscores in function names. Names in lowercases.
Use implicit parentheses to continue statements, instead of backslashes.
Add docstrings in classes.
[Lesson 08] Add blank spaces, underscores, remove backslashes.

Add blank spaces to make the code more readable.
Add underscores and lowercases in function names.
Remove backslahes and use implicit parenthesis to continue statement.
[Lesson 09] Add blank spaces, docstring, remove backslashes.

Add blank spaces to make the code more readable.
Add docstring to document (comment) functions and classes.
Remove unecessary backslashes and use implicit parentheses.
[Lesson 10] Add blank spaces, underscores, docstring, remove backslashes.

Add blank spaces to make the code more readable.
Add underscores in function names (lowercases).
Add docstring to comment functions and classes.
Remove unecessary backslashes and use implicit parentheses
to continue statements.
[Lesson 11] Add blank spaces, underscores, docstring, remove backslashes.

Add blank spaces to make the code more readable.
Add docstring to document functions and classes.
Add underscores in function names (lowercases).
Remove backslashes to use implicit parentheses to continue statements
on multiple lines.
[Lesson 01] Remove loops to use the pythonic way directly.
Change some code comments.
[Lesson 02] Change to lowercase/underscore for variable names. Add docstring in functions.

Change variable names with the convention lowercases and underscores.
Add docstring (and explanation about it) in functions.
[Lesson 03] Change variable names. Add docstring.

Change variable names with the lowercase/underscore convention.
Add docstring to the functions.
[Lesson 04] Change variable names. Add docstring to functions.

Change variables names with the lowercase/underscore convention.
Add dosctring to the functions.
[Lesson 06] Change variable names. Add docstrings.

Change variable names using the lowercase/underscore conventions.
Add dosctring to the different functions.