Renamed MemoryMapListEntry struct to MemoryBlock.

The old name was just too long.
Changed MemoryBlock to a double-linked list.
Removed duplicate parameter check
Changed signature of MemZero/MemCopy.

Both functions now return the destination-pointer.
Changed function signature of StringCopy; Inlined StringCopy/StringAppend in crtString.h

StringCopy now no longer requires the number of bytes to copy. (And thus was the same as MemCopy)

Both StringCopy and StringAppend are now static inline'd in crtString.h, since they are exactly one line long.
Removed whitespaces at the end of some lines.
Changed function signature of the alloc/free function
Implemented Mem_PhysAlloc/Mem_PhysFree; fixed Mem_PhysMmSetup

It is now possible to allocate/free physical memory.
Freeing physical memory should be done rarly, since it causes memory fragmentation.