Add misc files to npm ignore

[SimonSchick]

Currently various redundant files are shipped to npm:

node_modules/zxcvbn/
node_modules/zxcvbn/.travis.yml
node_modules/zxcvbn/.zuul.yml
node_modules/zxcvbn/src/
node_modules/zxcvbn/src/adjacency_graphs.coffee
node_modules/zxcvbn/src/feedback.coffee
node_modules/zxcvbn/src/frequency_lists.coffee
node_modules/zxcvbn/src/main.coffee
node_modules/zxcvbn/src/matching.coffee
node_modules/zxcvbn/src/scoring.coffee
node_modules/zxcvbn/src/time_estimates.coffee

You might want to consider not shipping these files to reduce package size.

[SimonSchick]

FYI: This will roughly half your package size :)

[SimonSchick]

poke