This was an attempt to move saturating_arithmetic.zig to the "passing
for stage2" section, which did not pan out due to the discovery of 2
prerequisite items that need to be done, but I did make a bug fix along
the way of the calculation of max/min integers.
This commit also simplifies the saturating arithmetic behavior tests to
depend on less of the zig language that is not related to saturating
arithmetic.
Conflicts:
* doc/langref.html.in
* lib/std/enums.zig
* lib/std/fmt.zig
* lib/std/hash/auto_hash.zig
* lib/std/math.zig
* lib/std/mem.zig
* lib/std/meta.zig
* test/behavior/alignof.zig
* test/behavior/bitcast.zig
* test/behavior/bugs/1421.zig
* test/behavior/cast.zig
* test/behavior/ptrcast.zig
* test/behavior/type_info.zig
* test/behavior/vector.zig
Master branch added `try` to a bunch of testing function calls, and some
lines also had changed how to refer to the native architecture and other
`@import("builtin")` stuff.
