Sometimes framebuffer initialization failes

[chrlns]

In some startups it seems that the framebuffer cannot be initialized as expected. Reboot helps.

Perhaps a time issue, e.g. the ARM co-processor is too fast for the VC.

Ideas:

• Retry a few times if it fails.
• Wait a second after boot before initializing the framebuffer.

[chrlns]

Fixed with v0.0.3

Problem was that the heap was not in .bss but in .data.