Added a new tool that can be loaded into a user space darwin application and allows you

to find data on the heap. To use this, make the project and then when stopped in your
lldb debug session:

(lldb) process load /path/to/libheap.dylib
(lldb) find_pointer_in_heap (0x112233000000)

This will grep everything in all active allocation blocks and print and malloc blocks that contain the pointer 0x112233000000.

This can also work for c strings:

(lldb) find_cstring_in_heap ("hello")

llvm-svn: 148523