Fix typecast warning with -pedantic
Add basic testing
Add make target to run tests
Add tests for continuing after crash
Build tests with autotools
If tests crash, return non zero exit code
Add function for the library to guarantee freeing memory
Add tests for take_memory
Fix freeing stored pointers

Do it after test is run, no matter whether we are forking or not.
Document the take_memory facility
Fix a typo
Mention header in documentation