Electron upgrade

[alfred-landrum]

We should update Electron to most recent stable release, v10.1.1 currently. @jameskerr notes that last time we attempted an Electron upgrade, we had some issues with the Spectron framework, so the Electron update may require updating several other dependencies. (electron-userland/spectron#631)

[philrz]

The plan is to get the work for this prepared at the same time we're doing other work for the v0.18.0 milestone but hold back on merging it. This way we can merge it as we're starting work on the following milestone (presumed v0.19.0) and hence have all of those two weeks to continue testing with it.