Add --verbose flag to reduce logging to warning+ level, Add spinner

[x0rw]

now it looks clean but deserted,
So i added a simple spinner (|/-\) during build to give a sense of progress, especially when output is minimal.

There’s definitely room for more improvements in the output, but this is a good start.
Give it a try!
Resolves #66

[PLeVasseur]

Thanks for taking this on @x0rw! See my comment below.

In addition, one thing that I think would be useful to see fixed as a part of this is to remove this output:

checking consistency... No missing required field
No missing required field
No missing required field
No missing required field
No missing required field
No missing required field
No missing required field
No missing required field

[PLeVasseur]

Rather than a spinner, I think it'd be nice to share both:

• % through processing guidelines
• x/n through processing guidelines

Where the % and x/n could be derived from the guidelines being rendered. Probably to also highlight where at in the stages of guidelines processing.

[x0rw]

Originally i did what you just suggested manually but it builds so fast that using a progress bar gets overriden or broken or actually slowing down the build(threading issues) so i went back to this minimal version.
But i can use this tqdm python library to take care of these issues in the next commit.

[PLeVasseur]

Ah got it. If you can get it working with tqdm that's great. Let's revisit when you've given that a try.

[x0rw]

@PLeVasseur -- It works well, i got a hang of it now -- don't mind the repetitive code at the top and the imports i wll clean them up tomorrow, there is a sleep(0.1) after every progress bar for testing, run with ./make.py -c don't run with -v as those verbossy debugging logs break progress bars, i will disable them later,
i will personally perform a sleep(25200) now.