Fixed #define typo

DDDS_THREADS_SINGLE should have been DDS_THREADS_SINGLE in three places.
I initially committed this to develop, realized the error of my ways, reversed it, made a
branch "define-typo", and committed to this instead.
Merge pull request #7 from sorenhein/define-typo

Fixed #define typo in Scheduler.cpp
Deleted README in favor of README.md

No point in maintaining both
Merge pull request #8 from sorenhein/no-readme

Deleted README in favor of README.md