bitbake/parser,build,utils:

bitbake/parser,build,utils:
    We compile strings into code. In case of erros the traceback
    is not useful at all. It doesn't print the function name,
    accurate line number etc.
    Introduce a better_compile method that excepts the Error
    and prints the surrounding lines of code.
    We make use of it on the parsing level and execution level
    of python methods.