Change outpointTransactionHash to outpointTxId and enable it and all introspection opcodes

[someone235]

Closes #175

Enable the remaining transaction input introspection fields and align their names and types with the underlying opcodes.

Language Behavior Changes

• Rename outpointTransactionHash to outpointTxId.
• Add the sequence input field.
• Expose outpoint transaction IDs as byte[32].
• Expose input sequences as byte[8].
• Support the complete input introspection field set.

int i = 0;

int value = tx.inputs[i].value;
byte[] scriptPubKey = tx.inputs[i].scriptPubKey;
byte[] sigScript = tx.inputs[i].sigScript;
byte[32] outpointTxId = tx.inputs[i].outpointTxId;
int outpointIndex = tx.inputs[i].outpointIndex;
byte[8] sequence = tx.inputs[i].sequence;

The previous outpointTransactionHash field name is no longer accepted.