Show Transaction name for TokenScript defined transactions in transactions history view

TokenScript allows you to define your own contract transactions.

Currently these will appear as default 'Send' transactions usually with zero amount.

Inside the TS file you can see transactions defined as such:

```

```
There is a function within the TokenScript parser to produce the ethereum function definition from this description. From there, the function prototype string could be produced in this case

```giveBirth(uint256)```

Which can be hashed using ```TransactionDecoder.buildMethodId``` to get the ten digit hex signature.

When a transaction is expanded in TransactionHolder, the leading 10 bytes of the transaction can be checked against these hashes from the TokenScripts, and if we get a match we can display the called function name.