Move the values interfere function to belive.h, move the inline
implementation into belive.c

It has been empty for nearly all systems. People who used to put stuff
in config.h can still create a config.h on their own and inject
-include (gcc) or /FI (msvc) into their CPPFLAGS.

- Avoid the quite expensive be_ifg_degree().
- Check while collecting the neighbours, instead of first collecting all, then testing whether they form a clique.

Just state the copyright and the project the files belong to. You can
then find the COPYING file for the whole project.

(no changes in functionality)

Fix the size reduction stuff which happily assigned non-allocatable
registers. It worked by chance on x86 as all non-allocatable registers
come last.

This tries to get the names in a consistent format. We basically have 2
views on register allocation/constraints now:

1) Register Requirements and Assigments are per-instruction. Each
   instruction has requirements on its inputs and outputs, register get
   assigned for outputs of an instruction (assignment is an attribute of
   an instruction, not of the Proj-nodes).
   The internal datastructures model this form!

   The functions here have the form:
     arch_get_irn_register_req_in(node, input_nr)
     arch_get_irn_register_in(node, input_nr)
     arch_get_irn_register_req_out(node, output_nr)
     arch_set_irn_register_out(node, output_nr, register)

2) Register Requirements and Assignments are on firm-values. This view
   allows to query/assign requirements and registers at the Proj nodes
   instead of the repsective predecessors.
   This is a convenience interface modeled on top of the other!

   The functions have the form:
     arch_get_irn_register_req(node)
     arch_get_irn_register(node)
     arch_set_irn_register(node, register)

adapted to changes

[r27702]

[r27693]

[r27647]

[r27277]

[r27153]

[r27145]

[r26468]

[r26317]

[r22985]