Fixes opt/fehler204 again.

Extend opt_manage framework with MANY_RETURNS condition.

Since normalize_n_returns might introduce unreachable code,
the order should be handled in the framework instead of the
optimization.

Fix opt/gap test.

Newer yComp (>= 1.3.14) can handle backslashes in strings.

Fixes test opt/fehler204

Dump array initialisers, which contain only bytes in the printable range, as strings instead of separate byte initialisers.

Eg.
[0] = 0x62
[1] = 0x6C
[2] = 0x61
[3] = 0x00]
becomes
[0...3] = "bla<NUL>"

TODO: Fix yComp, so it does not choke on backslashes.

It is just an unnecessary node, which the middleend does not understand and therefore cannot optimize.

Most of the world can handle C99 now, and the important rest (=msvc) can
handle long long as an extension.

They have been unnecessary aliases for is_SymConst_addr_ent() and
get_SymConst_entity().

The new interface uses no complicated callbacks anymore, but is a simple
ir_node* -> void* nodemap. Adapted all users of ir_phase for this.

From the manpage: If c is not an unsigned char value, or EOF, the
behavior of these functions is undefined.
(So putting char into them directly is wrong)

This simplifies the code and should make it slightly faster