Bug fix and performance improvement:
- Taylor variable: private ctor moved to public to enable compilation with clang
- Addition operator: isOneOrZero functionality is commented since it is performance bottleneck.


git-svn-id: svn://svn.code.sf.net/p/acado/code/trunk@155 f4037fd0-e48f-4cc9-9f8e-e12ed3b76bf3