deps: connect@2.27.0
deps: debug@~2.1.0
deps: depd@~1.0.0
deps: send@0.10.0
deps: jade@~1.7.0
build: misc. updates to packaging

closes #2398
Use content-disposition module
Use etag module to generate ETag headers
3.18.0
deps: mocha@~2.0.0
deps: should@~4.1.0
Fix internal utils.merge deprecation warnings
deps: connect@2.27.1
deps: send@0.10.1
3.18.1
Merge tag '3.18.1' into 4.10