adding week2 material

codeExamples/week2/.gitignore

codeExamples/week2/SampleWebpage.html

codeExamples/week2/add.js

codeExamples/week2/commandLineAsync.js

codeExamples/week2/commandLineSync.js

codeExamples/week2/eventEmitterExample.js

codeExamples/week2/eventLoop.js

codeExamples/week2/eventsExample.js

codeExamples/week2/httpExample.js

codeExamples/week2/httpFile.js

codeExamples/week2/index.js

codeExamples/week2/osExample.js

codeExamples/week2/package-lock.json

codeExamples/week2/package.json

codeExamples/week2/pathExample.js

codeExamples/week2/raise.js

lectures/week2/Express Intro.pdf

lectures/week2/Javascript Intro Day 2.pdf