This is required to have latest version of Docker and build all its buildtime requirements

- macros.go: fix missing quotes in %goinstall (bsc#939067)

- macros.go: fix "summary-not-capitalized"

- macros.go:
* *-doc can't properly describe what the sub-package really is,
and they're mostly source codes instead of the claimed "API,
documentation, and examples". so rename to *-source. and not
recommend to install them to save users' disk space.
* %%go_requires should be handled automatically by golang-packaging
* not recommend to install source package any more,
so %%go_recommmends set to nil.

- macros.go:
* add a "WITH_FAKE_BUILDID" option to enable the fake build ID
compution.
* to fake build ID, you have to make sure your package has only
one binary. it is nonsense that two or more nonidentical
binaries have the same build ID.

- enable debuginfo
* the strip workaround (boo#818502) does not need any more
* re-enable debug_packge/debug_install_post macros
- add patch: go-1.4.2-rel.plt-alignment.patch
* cmd/ld: set alignment for the .rel.plt section on 32-bit architectures
* https://github.com/golang/go/issues/9802
* or i586 build will fail at extracting debuginfo
- macros.go:
* re-enable debug_packge/debug_install_post macros from goprep()
* add ldflags to gobuild() to compute BUILD ID for debuginfo package