[FIX] Removed dependency on RandomSolution header. Removed unnecessary calls to .get() method from smart pointers.

[ENH] [FIX] Added default values for BUILD_* local variables. Removed header from the list of lib4neuro source files.

[FIX] Removed 'filesystem' header causing problems with portability. CI pipeline on CentOS (issue #25) is active.

CentOS Dockerfile repo: git@github.com:MartinBeseda/centos-ci.git

[FIX] [Linux] Added space after '-j' flag. Added '-e' flag to 'echo' commands in *.sh build scripts to allow colors in the output.

an out-of-source build into the 'build' folder (see issue #20).

[ENH] [Linux] linux_gcc_build_x64_debug_system.sh script rewritten to perform out-of-source build in the 'build' folder (see issue #20).