Merge pull request #154 from slayoo/master

using Release mode in most places to economise memory usage
adding making tests in release mode to .travis.yml
adding static_assert to check the number of boundary conditions
adding more informative message to an exception
fixing concurrent_1d
set OMP_NUM_THREADS to 4 when running tests in .travis.yml
Merge pull request #155 from mwarusz/master

fixing some problems with tests in Travis (hopefully)
Update README
Merge branch 'master' of github.com:djarecka/libmpdataxx
Merge pull request #156 from djarecka/master

Update README