make parallel suffix sorting optional in Utf8String class
remove debug messages from utf8 wavelet tree construction
- remove debug message from SparseGammaGapFileLevelSet class
- make parallel suffix sorting optional in OctetString class
avoid unused variable warning by conditional compilation
do not use UNIQUE_PTR_MOVE on temporary objects (clang compatibility)
- check if sync ops are available on x86 without compiler options
- include omp pragma in openmp macro test. libgomp library functions
  are not available on Darwin without include omp pragmas
add rudimentary current memory usage info for Darwin
move code from assert statements so it is run when NDEBUG is active
improve error checking
add memory usage code for FreeBSD
- link against libkvm on FreeBSD
- include some methods in Chromosome for older compilers
- fixes for clang and unique_ptr
add configure options to deactivate sync ops
bump version after commits: fix compilation on Darwin, make code compile with clang