make npm package name lowercase for npm cli 2+ compatibility

npm cli enforces a lowercase package name, and so using the mixed case testMethodName() value fails this test with npm cli version 2+.

https://github.com/npm/npm/blob/v2.0.0/node_modules/normalize-package-data/lib/fixer.js#L312

23 verbose stack Error: Invalid name: "npmCliPublish"
23 verbose stack     at ensureValidName (/usr/local/lib/node_modules/npm/node_modules/normalize-package-data/lib/fixer.js:322:15)
23 verbose stack     at Object.module.exports.fixNameField (/usr/local/lib/node_modules/npm/node_modules/normalize-package-data/lib/fixer.js:211:5)
23 verbose stack     at CachingRegistryClient.publish (/usr/local/lib/node_modules/npm/node_modules/npm-registry-client/lib/publish.js:35:11)
23 verbose stack     at /usr/local/lib/node_modules/npm/lib/publish.js:124:14
23 verbose stack     at mapToRegistry (/usr/local/lib/node_modules/npm/lib/utils/map-to-registry.js:55:3)
23 verbose stack     at publish_ (/usr/local/lib/node_modules/npm/lib/publish.js:104:3)
23 verbose stack     at Array.1 (/usr/local/lib/node_modules/npm/node_modules/slide/lib/bind-actor.js:15:8)
23 verbose stack     at LOOP (/usr/local/lib/node_modules/npm/node_modules/slide/lib/chain.js:15:14)
23 verbose stack     at LOOP (/usr/local/lib/node_modules/npm/node_modules/slide/lib/chain.js:14:28)
23 verbose stack     at chain (/usr/local/lib/node_modules/npm/node_modules/slide/lib/chain.js:20:5)

Nexus validation though allows mixed case package names, and I see no reason to change this as the official common.js spec does not require lowercase.

http://wiki.commonjs.org/wiki/Packages/Registry#Changes_to_Packages_Spec