Fix broken typing

[guopengliang]

The types export seems to be broken. When using the default Expo typescript config expo/tsconfig.base, all methods imported has the any type instead of what was declared in the source codes.

The module import { ... } from 'rn-encryption' resolves to node_modules/rn-encryption/lib/typescript/module/src/index which has the following content:

// File: `node_modules/rn-encryption/lib/typescript/module/src/index.d.ts`

export declare const generateAESKey: any, encryptAES: any, decryptAES: any, encryptRSA: any, decryptRSA: any, generateRSAKeyPair: any, generateHMACKey: any, hmacSHA256: any, hmacSHA512: any, hashSHA256: any, hashSHA512: any, generateRandomString: any, base64Encode: any, base64Decode: any, generateECDSAKeyPair: any, signDataECDSA: any, verifySignatureECDSA: any, encryptAsyncAES: any, decryptAsyncAES: any, encryptAsyncRSA: any, decryptAsyncRSA: any, encryptFile: any, decryptFile: any, getPublicRSAkey: any, getPublicECDSAKey: any;
//# sourceMappingURL=index.d.ts.map

Maybe this is a library bundling issue?