Show the limit and attempted size when tx data size is exceeded

[danfinlay]

Currently, geth enforces a tx size of 128kb.

If a user exceeds this, they get a pretty useless error:

It's getting easier to exceed this with sites that allow massive transaction batching, like gem.xyz.

It would be nice if a user gets this error, for us to show a useful message on the failed transaction, like:

This transaction was 256kb, which exceeds the limit of 128kb