Solved example 7.7

Circle function in utils.py was also broken
Revert "Solved example 7.7"

This reverts commit b17ea29b23cbcf41c7a81e1036b4f699f03a6d49.
Solved example 7.7
Applied PEP8 to example 7.6
Merge pull request #78 from bsaaiman/master

Example 2.2, allowable delta's from page 262, two interactive transfer function examples
Merge pull request #79 from Fugacity59/master

Solved Example 7.7
Solved example 2.9
Merge pull request #80 from Fugacity59/master

Solved example 2.9
Changed step function in example 2.9
Merge remote-tracking branch 'upstream/master'
Added exercise 5.9
Merge pull request #81 from Fugacity59/master

Changed step function in example 2.9
Merge pull request #82 from kyliefenner/master

Exercise 5.9
Merge pull request #3 from alchemyst/master

Updating repo