process.env accessor functions.
npm install env-accessors   
> process.env accessor functions.
$ npm install env-accessors --save
###### .del
> aliases: -
Delete given key from process.env.
del('DISABLED_SERVICES');
###### .get
> aliases: -
Get given key's value from process.env.
get('DATABASE_NAME');
###### .has
> aliases: contains
Whether process.env contains given key.
has('NEW_RELIC_LICENSE_KEY');
###### .missing
> aliases: -
Whether given key is missing from process.env.
missing('NEW_RELIC_LICENSE_KEY');
###### .required
> aliases: assert
Throw a ReferenceError if given key is missing from process.env and return given key's value from process.env otherwise.
required('NEW_RELIC_LICENSE_KEY');
###### .set
> aliases: put
Set value for process.env[key].
set({ DATABASE_HOST: 'localhost' });