Fix trace :encapsulate nil.

Non x86oids had a regression since ea26488.

And x86oids were always broken when it came to stacked return values,
using the wrong offsets.
And x86-64 was broken because of the N-FIXNUM-TAG-BITS change.
another test for interleaved raw slots and make-load-form

from Douglas Katzman
1.2.6: will be tagged as "sbcl-1.2.6"
modify release.sh for new SourceForge urls
One IF is clearer than three.
Unify the compiler macros for WRITE and WRITE-TO-STRING
Make disassembler correctly detect multiple code .ENTRY points

If pad bytes were inadvertently decoded as opcodes, they might bump
the PC beyond where the fun-header-widetag is, and so the .entry hook
would fail to trigger, and everything would be wrong until by chance
the decoder could sync to a valid opcode.

And the use of sb!kernel:code-header-ref in 'add-fun-header-hooks'
was insane. SEG-CODE could be NIL, but it "worked" to dereference NIL
as if a code-header and get back NIL by random coincidence.
Assorted PCL sanity improvements

- PRINT-OBJECT on methods was ugly because it could use
  print-unreadable-oject inside print-unreadable-oject
- PRINT-OBJECT on a GF (or any named thing) should show the
  address too if the name is not a proper name for the object.
- PRINT-OBJECT on a cache was totally wrong
- CHECK-GF-LAMBDA-LIST is expressed slightly better
Avoid generic math in INFO-GETHASH
Use one fewer variable in SB-PCL::EMIT-CACHE-LOOKUP

and sprinkle some comments around.
Fix lp#1397454 - invalid PCL ctor optimization.
Recognize self calls during xc.

DEFUN needs to expand into NAMED-LAMBDA, and IR1-CONVERT-LAMBDALIKE
shouldn't recognize calls to functions with transforms or templates as
self calls, otherwise (defun car (x) (car x)) breaks.
Simplify WALK-METHOD-LAMBDA and consumers thereof.

The earliest PCL releases had many different ways to expose CALL-NEXT-METHOD
(named ADD-LEXICAL-FUNCTIONS-TO-OPTIMIZED-n for n=1..6) depending on whether
it was ever an operand to FUNCTION in a particular method and/or whether the
method always, sometimes, or never passed arguments to CALL-NEXT-METHOD.
(And a local macro binding was generally favored over a local function)
In contrast, the 'closurep' flag served no purpose in SBCL, and by providing
NEXT-METHOD-P gratuitously, there is no need to pre-scan for uses of it.
Avoid putting two safepoints in a row when doing self calls.

Because it's a loop it needs a safepoint, but there's already one at
the beginning of a function.
Restore exception handling on Windows-x86.

GCC decided to change its default stack alignment to 16 bytes, and now
we depend on aligning SAPs on the stack, the exception_handler_wrapper
assembly wrapper didn't maintain 16-byte stack alignment causing
problems. Fixing exception_handler_wrapper would be easy, but SBCL
only observes 4-byte alignment on x86oids, so it's better to convince
GCC with -mpreferred-stack-boundary=2 (and wait until we have the same
problem on Linux).
Restore effectiveness of *FGENS* cache (as mentioned on sbcl-devel)
Add MAKE-SEQUENCE transform
Trivial change of some DEFVARs to DEFGLOBAL
Sometimes allow MAPCAR et.al. to see compiler-macro for the funarg
Enhancement to help detect wrongly-ordered lists of files to compile.