Implement software updates

[bbondy]

• Implement software update server
• Support multi channel releases
• Implement client side software updates for macOS
• Implement client side software updates for Windows
• Create documentation for server and client update process

[RyanJarv]

Sorry for the lack of updates here.

Currently focusing on implementing the client side in an effort to reduce risk of building any infrastructure we won't need. Once we are making progress there or I can hand that off I'll move on to the backend.

OSX client status:

• @simonhong has the initial sparkle implementation in brave/brave-core#91
• Working on some testing and automation in https://github.com/RyanJarv/updater currently

Windows client status:

• Working on the getting the build environment set up. Have been making progress but have run into plenty of issues here. Also making a packer/vagrant config so this can be handed off easily and will pull in people once I have that setup.

Crash reports:

What https://github.com/crystalnix/omaha provides for this is fairly simple and is meant to integrate with other services for search and indexing. I don't believe there's much of a reason to migrate from what we have currently as apart of this project and may also make sense to look into using other services like Sentry directly (they recently added support for crashpad dumps).

Software update server:

Going to be working on this after we're making progress on the implementations but looked into this a bit and ran into issues with the production config that is available in https://github.com/crystalnix/omaha. Wanted to come back to that and evaluate if we want to do something different there, not too worried about this being a risk right now though.

[bbondy]

Thanks for the updates @RyanJarv , I pinged Aubrey and Matt O. about helping with the crash reporting.

[RyanJarv]

@bbondy, @simonhong has brave/brave-core#91 ready to be merged with updates disabled.

There are some outstanding issues but sec has given the ok as long as we take care of them before we enable updates (https://github.com/brave/internal/issues/274).

[RyanJarv]

Closing this in favor of #179 for the client implementation and brave/omaha-server#1 for the server side.

[srirambv]

Verification Passed on

Brave	0.55.6 Chromium: 70.0.3538.16 (Official Build) dev (64-bit)
Revision	16ed95b41bb05e565b11fb66ac33c660b721f778-refs/branch-heads/3538@{#306}
OS	Linux

• Installed 0.55.5 via instructions on https://brave-browser.readthedocs.io/en/latest/installing-brave.html#linux
• Ran sudo apt update once 0.55.6 was availabe
• Ran sudo apt upgrade prompted to upgrade brave
  

Verification Passed on

Brave	0.56.1 Chromium: 70.0.3538.22 (Official Build) dev (64-bit)
Revision	ac9418ba9c3bd7f6baaffa0b055dfe147e0f8364-refs/branch-heads/3538@{#468}
OS	Windows 7

Verified passed with

Brave	0.55.6 Chromium: 70.0.3538.16 (Official Build) dev (64-bit)
Revision	16ed95b41bb05e565b11fb66ac33c660b721f778-refs/branch-heads/3538@{#306}
OS	Mac OS X

• downloaded .dmg file for 0.55.6. Navigated to chrome://settings/help. Got Relaunch button. After relaunching (manually) I was updated to 0.56.1.