Implement operator=(initializer_list) like initializer_list constructor
Add int vector
Add test_vec.cpp from kurskatalog
Recode test_vec.cpp to UTF-8
Enable one more test in test_vec.cpp

And comment out one line which is not supposed to compile
Flesh out AssignmentOperatorSelf test
Add make targets for running test_vec in valgrind

    $ valgrind --tool=memcheck --leak-check=yes --track-origins=yes ./test_vec

    ==18017== Memcheck, a memory error detector
    ==18017== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
    ==18017== Using Valgrind-3.9.0 and LibVEX; rerun with -h for copyright info
    ==18017== Command: ./test_vec
    ==18017==
    ==18017== Warning: client switching stacks?  SP change: 0xbec5a6b0 --> 0x4022f9c
    ==18017==          to suppress, use: --max-stackframe=1161595116 or greater
    ==18017== Warning: client switching stacks?  SP change: 0x4022f9c --> 0xbec5a6b0
    ==18017==          to suppress, use: --max-stackframe=1161595116 or greater
    Index out of range
    ==18017==
    ==18017== HEAP SUMMARY:
    ==18017==     in use at exit: 0 bytes in 0 blocks
    ==18017==   total heap usage: 129 allocs, 129 frees, 24,193 bytes allocated
    ==18017==
    ==18017== All heap blocks were freed -- no leaks are possible
    ==18017==
    ==18017== For counts of detected and suppressed errors, rerun with: -v
    ==18017== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
Add int vector code for Lab1 task 1.4

Ref issue #6: Lab1 1.4: Vector
https://github.com/ZetaTwo/dd2387-laborationer/issues/6