add standard files to gitignore
update examples to use new bitcore interface

These are the same examples in the bitcore code, but updated to reflect how
they would be used by someone who ran "npm install bitcore"

...e.g., using ./node_modules/PeerManager instead of ../PeerManager
remove unnecessary newlines
Merge pull request #142 from ryanxcharles/feature/update-readme-examples

Add and update examples to reflect new bitcore interface