Updated development dependencies

v1.3.4

Security update: Updated dependencies

Updated version of chai and mocha

New padding when encoding trytes to bytes

Bug #5 made it clear that the padding values had important drawbacks.

Version 1.3.0 fixes this drawback, but leaves trytes encoded in bytes in v1.2.0 incompatible with decoding in v1.3.0 or later.

The padding byte is used for any length that is not divided by 5. Thus, IOTA seeds of 81, will be affected by this fix.

Added Unicode to tryte strings

New feature: Encode and decode any Unicode text string as a tryte string, using BOM to indicate ASCII, UTF-8 or UTF-16.

Encoding bytes as trytes

Decode bytes to trytes, can only take bytes in 0-242 range (tryte5).

If you have native bytes, in the full range of 0-255, you need to convert them to a tryte6 (0-728).

Encoding trytes as bytes

First release encodes tryte strings (9 + A-Z) into bytes, and back.

The strings containing tryte3 characters, are shifted into a tryte5 (0-242), and treated as bytes.