const env = require('sugar-env')
    env.current: string
      ✔ returns the current environment's name (from NODE_ENV)
      ✔ returns "development" when `NODE_ENV` isn't set
    env.DEVELOPMENT: string
      ✔ returns development's environment name: "development"
    env.TEST: string
      ✔ returns test's environment name: "test"
    env.STAGING: string
      ✔ returns staging's environment name: "staging"
    env.REVIEW: string
      ✔ returns review's environment name: "review"
    env.PRODUCTION: string
      ✔ returns production's environment name: "production"

  const env = require('sugar-env')
    env.is(environment: string): boolean
      ✔ returns `true` when the current environment name is the one specified
      ✔ returns `false` when the current environment name is different than the one specified
    [ DEPRECATED ] env(a: String).is(b: String): boolean
      ✔ returns `true` when "a" is equals "b"
      ✔ returns `false` when "a" is different than "b"

  const env = require('sugar-env')
    env.get(envVarName: string): string
      ✔ returns `null` when the environment variable doesn't exist
      ✔ returns `null` when the environment variable's value is empty
      ✔ returns the environment variable's value when it exists and it isn't empty
    env.get(envVarNames: string[]): string
      ✔ returns the value of the first environment variable which contains a non-empty value
    env.get(envVarName: string | string[], defaultValue: string): string
      ✔ returns `defaultValue` when the given environment variable doesn't exist
      ✔ returns `defaultValue` when the given environment variable's value is empty

  const env = require('sugar-env')
    env.get.boolean(envVarName: string): boolean
      ✔ returns `true` when the given environment variable's value is "1"
      ✔ returns `true` when the given environment variable's value is "true" (case insensitve)
      ✔ returns `false` for anything else
    env.get.int(envVarName: string): number
      ✔ returns `null` when the given environment variable is missing
      ✔ returns `null` when the given environment variable's value is empty
      ✔ returns `NaN` when the given environment variable's value isn't an integer
      ✔ return a `number` when the given environment variable's value is an integer
    env.get.float(envVarName: string): number
      ✔ returns `null` when the given environment variable is missing
      ✔ returns `null` when the given environment variable's value is empty
      ✔ returns `NaN` when the given environment variable's value isn't numeric
      ✔ returns a `number` when the given environment variable's value is numeric
    [ DEPRECATED ] env.get.url(envVarName: string): string
      ✔ returns `null` when the environment variable's value is missing
      ✔ returns `null` when the environment variable's value is empty
      ✔ returns the environment variable's exact value when there is already a trailing slash
      ✔ returns the environment variable's value with a trailing slash
    env.get.base64(envVarName: string): string
      ✔ returns `null` when the environment variable doesn't exist
      ✔ returns `null` when the environment variable's value is empty
      ✔ returns the environment variable's value after decoding it from base64

  const env = require('sugar-env')
    env.has(envVarName: string): boolean
      ✔ returns `true` when the given environment variable exists
      ✔ returns `false` when the given environment variable doesn't exist