huge refactoring

MAJOR refactoring in memmanager. Optimized object handles from 5 words
to 4 and gc speed improved. Fixed float pow bug.
Added dict.dasm16
mem() function to run gc and return free heap
mem() function to run gc and return free heap
realloc refectoring and still drafting floppy
fixed realloc bug, added startup screen

...yes I know - startup screen only wastes memory :-(
Bug Fix: Startup says "words" not "bytes"
finetuning memory layout setup
Update admiral.dasm16
finetuning memory layout
Update README.md
Merge branch 'master' of git://github.com/orlof/dcpu-admiral