OpenBMC v1.99.0 tag.

I created the first tag towards a 2.0 release, called 1.99.0. This tag is intended to be a (very early) development pre-release to show some of the progress being made towards 2.0. I will continue to make these tags on a periodic basis when I think there is significant function as well as some stability.

This specific tag has been tested on the Barreleye and Palmetto systems and should still function. Rebooting the BMC while the Host is powered on is known to not work on some machines due to openbmc/openbmc#513.

The main significant functionality in this release is:
- Kernel upgrade to 4.7.x stream.
- Yocto upgrade to 2.1.

There are two main reasons for the 1.99.0 tag:
- Current /etc/os-release files have a git revision of the form 1.0-N, which is confusing relative to the 1.0.x stable release stream.
- There is a significant patch-set in Gerrit that I will be merging soon, which migrates all BMC state management to a systemd basis instead of custom Python script states.

Again, do not use any 1.99.x tag for production purposes. Please, do feel free to test with it and report problems.

Patrick Williams