setup.py

Besides calls between libaries (i.e., library A imports library
B and calls a function in B) we also need to keep track of calls
inside the respective libraries (an exported function inside
library B can call another exported function).

In order to generate these call graphs, this change uses capstone
to disassemble all exported functions (defined by their address
ranges) and checks all jump and call instructions if they point
to a known exported function.

The current release of capstone fails to disassemble instructions
with the 0x66 prefix as well as movsxd instructions; in this case
we use a fallback to objdump to disassemble this code and 'parse'
it via regular expressions - this pattern is quite rare, so it
should not have a too great impact on performance but gives us
more exact results.