GitLab

- ADDITIONAL_TARGETS changed to a list for flexibility
- more checks/flexibility with find_program
- separate, correct gdbinit file for QEMU
- debugger, RAM, gdbstub port configurable
- build .iso files only when needed and with correct path
- nogui bochs config

Change-Id: I396ad782d7e47b3c6636123d930390b204d275a6

Note: test output cannot be passed to CTest yet, so all tests pass...

Added CMake macros to generate bootable elf files
Created test runner "framework" with supporting CMake macros
Disabled rebooting on triple-fault for bochs and qemu to exit after test
Adjusted existing scheduler dequeue test

closes #30

Change-Id: I82955242cbb3623b68cb590943d4d4e7c995c8cc

TODO: setup target and platform only via cmake_toolchain