Travis recently appears unable to find a matching homebrew package for 32bit gfortran,
and the IOS crossbuild suffered from excessive output due to the known problem with "ASMNAME redefined"
warnings when CFLAGS is set in the environment

* Add automatic fixups for OSX/IOS cross-compilation

* Add OSX/IOS cross-compilation test to Travis CI

* Handle platforms that lack hwcap.h by falling back to ARMV8

* Fix PROLOGUE for OSX/IOS

os version 10.13 "High Sierra" appears to be the oldest release now for which Homebrew provides a gcc package.
Anything older and the Travis job will run out of time building gcc from source

in response to Homebrew updates

as this semi-official beta option has suddenly reverted to a standard x86_64 environment causing spurious failures

* remove some of the steps & comments
from the original Azure yml template

* modify the trigger section to use
develop since OpenBLAS primarily uses
this branch; use the same batching
behavior as downstream projects NumPy/
SciPy

* remove Travis emulated ARMv6 gcc build
because this now happens in Azure

* use documented Ubuntu vmImage name for Azure
and add in a manylinux1 test run to the matrix

[skip appveyor]

* add native POWER8 testing to
Travis CI matrix with ppc64le
os entry

as xcode10 deprecated i386

as homebrew seems to have dropped support for El Capitan in their gcc packages

Updated `.travis.yml` file to add emulated tests for `ARMV6` and `ARMV8`
architectures with `gcc` and `clang`.  Created prebuilt images with
required dependencies. Squashed layers into one.

* Prefix make with travis_wait to prevent it getting killed for producing no output

* Extend travis_wait to 30mins for the windows build

* Trying 45 mins wait time

* Increase travis_wait time to 45 minutes for linux builds as well

,,,to see if this has any influence on the recent ld SIGKILLS

https://github.com/xianyi/OpenBLAS/pull/1255#issuecomment-320494610

See: https://github.com/xianyi/OpenBLAS/pull/1255#issuecomment-318692183

See: https://github.com/xianyi/OpenBLAS/pull/1255#issuecomment-318628666

Alpine jobs needs sudo (for chroot), so they run on VMs infrastructure.
That's why they are much slower than other jobs.

Using APT addon has nice side-effect - you don't need sudo anymore, so
it can run on Travis containers-based infrastructure that is much faster
than their VMs infrastructure (used when sudo is needed).

You've been still running on Ubuntu Presty builders, but new default is
Trusty. Thus I've explicitly set `dist: presty` to let it stay on
Presty, to not change build environment by this commit.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>