env-var

• The required() function now verifies the variable is not an empty string

• Ability to add custom accessors in PR #72 (thanks @todofixthis)
• Improved TypeScript tests
• Fixed warning generated by husky

• Return values from asArray() are now more intuitive & consitent
• asUrlString() and asUrlObjectnow use the built-in URL class in Node.js
  to perform validation
• README updated in accordance with changes listed above

• Add asPortNumber() function
• Update documentation structure

• Add node process.env typings to env.from

• Rename .env.mock() to env.from()
• Change module internals per issue #39
• Update docs related to env.mock

• Update required() to support boolean parameter to bypass the check

• Fix README badge copy/paste error

• Fix TypeScript definition for "asBoolStrict" function name

• Add convertFromBase64() function
• Enable Greenkeeper

• Add asEnum functionality

• Remove @types/node dependency

• Update typings to correctly handle default values for numeric types.
• Ensure an error is thrown when asArray does not detect at least a single non-empty value.

• restore support for browser based applications

• Fix bug that caused default values to be ignored

• Public API no longer is a function, instead exposes two functions, mock and get
• Drop support for Node.js versions less than 4.0
• Rename asPositiveInt to asIntPositive
• Rename asNegativeInt to asIntNegative
• Rename asStrictBool to asBoolStrict
• Add asFloatPositive and asFloatNegative
• Add asUrlString and asUrlObject
• Refactor code with consistent errors and structure
• Use standard for code quality and formatting

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