Starter project code for students taking Udacity ud120 (updated to Python3)

Overview of changes:

• Shebangs changed to python3
• Parentheses around print statements
• Pickle files opened in binary mode for read/write
• Library updates like urllib and cPickle
• Language core changes like translate
• Occasional Python3 syntax helper comments

Software version numbers (2020-07-23):

• Python: 3.7.5
• GCC: 4.9.2
• scikit-learn: 0.23.1.
• nltk: 3.5.
• numpy: 1.18.5.
• matplotlib: 3.2.2.

Note: One file is also required for the completion of this course which contains mails from enron dataset, folder named as 'maildir' which can be downloaded by running startup.py

Also, if anyone get stuck somewhere they can take help from the solution repo provided: https://github.com/abhiishekporwal/ud120-projects-solutions