Fix a few typos and errors in the problem statements and type signatures
Merge pull request #5 from leonardoborges/master

Fix a few typos and errors in the problem statements and type signatures
Add more examples to Parser
Merge pull request #8 from ambiata/topic/additional-examples

Add more examples to Parser
Optional should be exercises
Id should be an exercise
Spelling
Merge pull request #14 from ambiata/topic/exercises

Topic/exercises