Enhance vis_heap_chunks (#625)
Enhance vis_heap_chunks (#625)

* Bin annotations
 * ASCII representation
 * Addresses formatted w/o ':' (ease terminal copy/paste)
 * Implicit addr support (pwndbg> vis_heap_chunks)
 * Use top_chunk as sanity end-of-heap check, making it easier to use
   during non-top_chunk heap corruption
 * Added --naive (-n) to disable end-of-heap check
 * Swapped arguments:
   pwndbg> vis_heap_chunks addr count -> vis_heap_chunks count addr
   Arguably, desired number of chunks v. heap addr is more readily
   available
pwndbg/pwndbg,pwndbg/pwndbg,cebrusfs/217gdb,cebrusfs/217gdb,anthraxx/pwndbg,pwndbg/pwndbg,anthraxx/pwndbg,pwndbg/pwndbg,anthraxx/pwndbg,cebrusfs/217gdb,cebrusfs/217gdb,anthraxx/pwndbg