Fix typo in routes/problem.md.
Merge pull request #31 from linclark/typo

Fix typo in routes/problem.md.
Use program.js instead of server.js.
Merge pull request #32 from linclark/filename

Use program.js instead of server.js.
Add exercise for directories.
Add failure if status code is 404 in directories exercise.
Add exercise for handling.
Make handling/problem.md more concise.

This wording brings it more in line with the style of learnyounode.
Make directories/problem.md more concise.
Show output instead of failure when in 'run' mode in directories.
Show output instead of failure when in 'run' mode in handling.
Indicate correct file name in handling/problem.md.
Add exercise for views.
Merge pull request #33 from linclark/directories

Add exercise for directories.
Merge pull request #34 from linclark/handling

Add exercise for handling.
Merge pull request #35 from linclark/views

Add exercise for views.
Add Lin Clark to AUTHORS.
Merge pull request #37 from linclark/authors

Add Lin Clark to AUTHORS.
merge