Parse and load local dapps directly from filesystem (#141)
* Set electron name to 'Parity-UI' Electron stores the user data by default in `~/.config/<app name>` The app name is retrieved from the package.json when Electron is run on a folder (e.g. `electron .`); default app name 'Electron' is used if Electron is run directly on a script, as is the case. Electron can be run either on .build/ or on .electron/ (dev), so it's not practical to use package.json to set the app name (.electron/ has no package.json); hence it's better in our case to define it in the code. * Parse & load local dapps directly from filesystem (userData folder) * Fix dapp icon URL * Remove synchronous file operations * Reorganise util/host.js * Fix tests * Use package.json to get Electron app name * Remove unused arguments