[pkg-go] Fixed golang-x-text package for go 1.5

[Martin Packman]

I've pushed up packaging changes to fix golang-x-text for golang 1.5
in experimental:

https://code.launchpad.net/~gz/+git/golang-x-text

If one of the debian go maintainers wants to review/adopt I would
appreciate it, will help me fix the package in wily.

Basically just new upstream snapshot and these debian/ changes:

https://git.launchpad.net/~gz/+git/golang-x-text/commit/?id=d59ffbf

I haven't chased down exactly why those test failures appeared, but
they cause ftbfs on both experimental and wily and the patch to avoid
is trivial.

Martin