Fixes CVE-2019-17596

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

Fixes CVE-2019-16276

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

Signed-off-by: Xingwang Liao <kuoruan@gmail.com>

Includes fixes (in 1.12.8) for:
CVE-2019-14809 - https://nvd.nist.gov/vuln/detail/CVE-2019-14809
CVE-2019-9512 - https://nvd.nist.gov/vuln/detail/CVE-2019-9512
CVE-2019-9514 - https://nvd.nist.gov/vuln/detail/CVE-2019-9514

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

Signed-off-by: Xingwang Liao <kuoruan@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

When installing a newer host Go, be sure to remove the old host Go. Not
doing so causes errors[1] when trying to build target Go.

[1]: https://github.com/openwrt/packages/pull/7194#issuecomment-435948361

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

Go 1.11 added softfloat support for 64-bit MIPS systems[1], so this also
adds builds for mips64 and mips64el.

[1] https://golang.org/doc/go1.11#mips

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

This also changes the bootstrap source URL to the official GitHub
mirror, to make building easier for places where Google sites aren't
accessible. Fixes #6326.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

From golang.org:
The Go programming language is an open source project to make
programmers more productive.

This commit consists of two "parts":

* golang/host: Main Go compiler for host (installed to
  STAGING_DIR_HOST/lib/go-cross), used to cross-compile Go programs to
  be packaged.

* golang (and golang-src/golang-doc): Main Go compiler for on-target
  development. These packages are quite large, but I would expect only
  developers to install these.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>