Added license information to README.md

Closes #610

…610

added comma
"If you're new to Git, take a look at..."

Fix grammatical error in README.md

forth: fix import line

markdown: Do not add <p> to list items

[This leap solution](http://exercism.io/submissions/7ef5b0ab93b540f79cdee9f153e0a21c) should not pass the unit test, since it checks whether `year % 100` and `year % 400` are equal in order to tell whether the year it has been passed is a leap year. This works for 2016 because `2016 % 100` and `2016 % 400` both evaluate to 16.

1996, another leap year that is divisible by 4 but not 100, does not have this property and, under that solution, would falsely not be classed as a leap year.

…s/python into implement-error-handling

Update to canonical-data v1.2.0: Swap '2016' for '1996' to stop faulty logic from passing unit test in Leap

complex-numbers: Fix spelling mistake

error-handling: implement exercise

Adds HINTS file to "rail-fence-cipher"
Adds HINTS file to "simple-cipher"
Adds HINTS file to "rotational-cipher"
Adds HINTS file to "robot-name"

…h Python2 and Python3 (#506)

* Update TESTS.md

Provides information on the different types of "pytest" available, as well as switched "py.test" to "pytest", as recommended here (pytest-dev/pytest#1629 (comment)).

* Fixed a typo.

* Small edit.

* Update TESTS.md

Cleaned it up, addressed what user "N-Parsons" commented on, fixed some errors, and added new information.

* Small Change to "PDB" Section.

…acks (#987)