Gas Price Must Be Greater Than Or Equal To 0.1 GWEI.

[luchua-bc]

When sending transactions to a private Ethereum blockchain like Quorum, there is no mining cost thus gas cost is zero.

However, MetaMask assumes all transactions have a non-zero cost thus doesn't allow to submit the transaction. It displays a warning and the SUBMIT button is disabled.

Could MetaMask offer the configuration to allow setting gas cost as 0 when connecting using the "Custom RPC" option?

The browser I used is Chrome 65 on iMac.

[nujabes403]

I modified this code on #4037

[danfinlay]

Closing as a duplicate of #3074.