ReadFile() implementation that works on Windows.

[abourget]

The Bytes() implementation breaks under Windows. This ReadFile could eventually simply replace it. It also is more similar to the stdlib's ioutil.ReadFile.

[abourget]

Sorry, this includes my previous PR (about OpenCloser()) .. it was to simplify my workflow! thanks :)

[GeertJohan]

Why isn't Bytes() working for you? An error or panic?

[GeertJohan]

Sorry, missed #45.

[GeertJohan]

I would like to see if Bytes() can be fixed, before adding a new method that essentially does the same..

[abourget]

Is there any optimization that Bytes() does that ReadFile misses ?

[abourget]

can we just swap the functions ? ReadFile() works in all conditions, where Bytes() crashes on Windows.

[abourget]

Ok, I've updated this PR to simply replace Bytes. Doesn't change semantics at all.

thanks!

[GeertJohan]

Thanks!

[GeertJohan]

I've actually also updated box.String() to use box.Bytes() when the data is not embedded.
(For embedded, there is no allocation required, it can just return the pointer to the embedded string)