Added changelog.txt to keep track of all changes. No functional changes this commit.
Added changelog.txt to keep track of all changes.
No functional changes this commit.

Signed-off-by: Zach Barth <4e84a6f43dab6f9587b990a2a84ad55aae41a442@gmail.com>
AlexMulkerrin/Infiniminer,ycaihua/Infiniminer