fix: export reader functions (#9)

Author: patrickmichalina

src/index.ts

@@ -1,3 +1,4 @@
 export { monad, IMonad } from './monad'
 export { maybe, IMaybe, IMaybePattern } from './maybe'
-export { either, IEither, IEitherPattern } from './either'
+export { either, IEither, IEitherPattern } from './either'
+export { reader, IReader } from './reader'

test/reader.spec.ts

@@ -1,4 +1,4 @@
-import { reader } from '../src/reader'
+import { reader } from '../src'
 
 describe('reader', () => {
   it('should of', () => {