Optimize webui for a great number of tokens

[kelsos]

Currently the webui is not build to handle a great number of tokens.

The first time the user opens the webui for each token 4 requests to web3 take place (decimals/name/symbol/balance).

Then as long as the user is in page the mechanism keeps polling for tokens every 5 seconds. The polling mechanisms also includes a call to web3 for each token to check for balance.

Possible steps to resolve this

• Update to web3.js 1.0.0 as we talked with @andrevmatos
• Find if it is possible to batch all these calls to web3 and instead of doing x (number of tokens) http requests use a single one for all the information.
• Find an alternative approach to update balances, instead of checking every 5 seconds

[kelsos]

The batching mechanism should not should not use the BatchRequest from web3.js since the class doesn't provide any promise based mechanism but instead works with callbacks. The initial approach using that mechanism also requires some monkey-patching to work and it is unnecessarily complicated.

The new mechanism should:

• Automatically split batched requests to smaller batches (RPC calls fail for more than 800 batched requests)
• Support for optional values with default return values. (In optional token properties the whole batch would fail due to an exception)
• Return a Promise that returns an array of all the results.
• Figure out when the batch promise should fail completely.