* Adds 4byte registry fallback to getMethodData() (#6435)
* Adds fetchWithCache to guard against unnecessary API calls
* Add custom fetch wrapper with abort on timeout
* Use opts and cacheRefreshTime in fetch-with-cache util
* Use custom fetch wrapper with timeout for fetch-with-cache
* Improve contract method data fetching (#6623)
* Remove async call from getTransactionActionKey()
* Stop blocking confirm screen rendering on method data loading, and base screen route on transactionCategory
* Remove use of withMethodData, fix use of knownMethodData, in relation to transaction-list-item.component
* Load data contract method data progressively, making it non-blocking; requires simplifying conf-tx-base lifecycle logic.
* Allow editing of gas price while loading on the confirm screen.
* Fix transactionAction component and its unit tests.
* Fix confirm transaction components for cases of route transitions within metamask.
* Only call toString on id if truthy in getNavigateTxData()
* Fix knownMethodData retrieval and data fetching from fourbyte
Abstract all configuration data into a singleton called `configManager`, who is responsible for reading and writing to the persisted storage (localStorage, in our case).
Uses my new module [pojo-migrator](https://www.npmjs.com/package/pojo-migrator), and wraps it with the `ConfigManager` class, which we can hang any state setting or getting methods we need.
By keeping all the persisted state in one place, we can stabilize its outward-facing API, making the interactions increasingly atomic, which will allow us to add features that require restructuring the persisted data in the long term without having to rewrite UI or even `background.js` code.
All the restructuring and data-type management is kept in one neat little place.
This should make it very easy to add new configuration options like user-configured providers, per-domain vaults, and more!
I know this doesn't seem like a big user-facing feature, but we have a big laundry list of features that I think this will really help streamline.
Also added the hdPath that Christian had told me to our calls to the LightWallet, but this does not seem to have made us generate the same accounts as `testrpc` yet.
