So that when it is installed e.g. via `go install` under gowork, the
binary name is "helloweb", not "go".

The code is now unified - it can work on both python2 and python3.

So it is less becomes less ambiguous when we update languages and check
them via helloweb.

Before:

    Hello world at `/`  ; Thu Jun  9 11:10:36 2016  (go)

After

    Hello world at `/`  ; Thu Jun  9 11:10:36 2016  (go devel +d66cbec Mon Jul 18 15:52:45 2016 +0000))

/reviewed-by TrustMe

Just for convenience. Before (e.g. for go):

    kirr@teco:~$ curl http://[::1]:7778
    Hello world at `/`  ; Thu Jun  9 11:09:49 2016  (go)kirr@teco:~$

After:

    kirr@teco:~$ curl http://[::1]:7778
    Hello world at `/`  ; Thu Jun  9 11:10:36 2016  (go)
    kirr@teco:~$

Python version already emits trailing newline, because it uses `print ...`
without trailing ",".

/reviewed-by TrustMe

Merge fixes to code formatting and naming as reported by gofmt and
golint from Gabriel.

see: !1

Following go conventions.

'go lint' is your friend

https://github.com/golang/lint

Effective Go: https://golang.org/doc/effective_go.html

helloweb.go:49:2: don't use underscores in Go names; var bind_ip should be bindIP
helloweb.go:50:2: don't use underscores in Go names; var bind_port should be bindPort
helloweb.go:51:2: don't use underscores in Go names; var bind_addr should be bindAddr

'go fmt' is your friend

https://blog.golang.org/go-fmt-your-code

Keep the same format is good to share and maintain code

Simple helloweb in Go that does the same as Python and Ruby versions.

/cc @gabriel, @Camata

Let's show how to do simple helloweb in Ruby. The program generates the
same output as Python version, only the comment about language is
different.

Comes with minimal gem specification, so it could be worked with /
installed via Bundler, together with dependency gems, if needed.

So far we use only stdlib without external gems.

/cc @kazuhiko

We'll soon have several helloweb programs written in different languages
with otherwise the same output, and it is better to distinguish them for
diagnostic.

So that it can be installed as egg/scripts via std setuptools machinery.

This is my simple program originally from slapos.git repository:

    nexedi/slapos@7cd2f953

with all follow-up changes to it in slapos.git tree.

A simple project showing how to say hello to the Web in different ways.