evas/png - better way to support png grayscale with transparency format.

suggested by cedric.
edje: textblock style loading changed

Summary:
Keeping "font=", "font_size=" and "text_class" in tag->value fixes
style loading issues (after saving edj file with edje_edit_save method).

Reviewers: cedric, raster, seoz, Hermet, tasn

CC: reutskiy.v.v, cedric

Differential Revision: https://phab.enlightenment.org/D940

@fix
Edje C++: Fix Edje.hh generation to update correctly.
ecore_evas: remove warning from Windows backend.
eina: use the right function prototype on Windows.
eina: silence warning of unused parameter on Windows.
ecore_win32: silent warning by reading the returned value in a useful way.
ecore_win32: another forgotten read that is unecessary in current setup.
ecore_con: just a reminder to look at later.
ecore_file: this parameter is indeed not used.
evas: silent some warning during Windows backend build.
evas: fix warning in DDraw backend.
evas: read fullscreen flags from initialized value.
evas: fix warning and remove useless code.
evas/gl: improve the rendering quality.

To avoid texture bleeding in the texture atlas,
we adjust texture uv point as much as a half uv point.
Especially, this improves the rendering quality when the image has the border
area.

Unless apply this patch,
You might find the rendering result is different with software backened,
if the image has the borders.

In the software backened,
the border line was clear but the gl wasn't.
because the border line was interpolated so the rendering result was not the one we expected.

@fix
evas/gl: fix indentation.
evas/gl - ... removed white trailing.
windows: make those warning explicit about what they imply.
lz4: fix possible security issue.

See :
- http://fastcompression.blogspot.fr/2014/06/lets-move-on.html
- http://www.openwall.com/lists/oss-security/2014/06/26/25

@fix
jpeg laoder: exif orientation test added

Summary:
currently, normal orientation tests are only added.
I'm going to add flipped orientation tests as well after I put related code in jpeg loader (currently it's not supported)

Reviewers: raster, cedric, jpeg

CC: seoz, cedric

Differential Revision: https://phab.enlightenment.org/D1098