Gitlab testing is introduced, using GitLab CI, to test many different configurations:
 - 32/64 bit architecture
 - float/double
 - 16/32/64 bit int size
 - none/NaN/word boxing
 - ASCII/UTF8

using various compilers:
 - gcc-4.7
 - gcc-4.8
 - gcc-4.9
 - gcc-5
 - gcc-6
 - clang-3.5
 - clang-3.6
 - clang-3.7
 - clang-3.8
 - clang-3.9