Create memory module

[vinc]

• Take unmapped and virtual memory into account when counting total memory
• Enable interrupts except keyboard during memory init to improve boot time accuracy
• Create mem module
• Move allocator inside mem module split into heap and phys
• Update memory usage command to report whole RAM usage

[vinc]

Allowing interrupt during kernel heap initialization correctly count elapsed time during the allocation, which can be slow with large memory. No adverse effects have been found yet.

[vinc]

Typing on the keyboard during memory init generates interrupts that crash the module. This can be fixed by delaying keyboard init to after memory init.

[vinc]

Except that loading the keyword module after memory initialization breaks it. Masking the keyword interrupt works though.

[vinc]

The memory usage command will now report whole RAM usage instead of only the kernel heap.