[gexiv2] GExiv2 and exiv2 0.26

[Jens Georg <mail jensge org>]

Hello,

Apparently exiv2 changed their stream io API with the 0.26 release cycle 
[1] which make GExiv2 fail to compile [2]

While the straight-forward solution would be to bump the requirements of 
GExiv2 to 0.26 and just follow the change
(for those in desperate need, there is a fix in Bugzilla [2])

I see three solutions:
 - Just go with it and require 0.26 for 0.10.x from now on
 - Start a new series, keep 0.10.x at <= 0.25, bump 0.11.x to 0.26 and 
add new soname
 - Make magic trickery with EXIV2_TEST_VERSION and provide whatever 
implementation exiv2 is using

Currently I am leaning to opening 0.11.x, while fixing similar issues in 
the io stream API as provided by GExiv2.

I would really like to know if there are actual consumers of the stream 
io api - it looks weirdish, is not
introspectable and probably better replaced by a GIOStream-based API.

So a switch to 0.11 should - IMHO - also include deprecation of the old 
API and providing a GIO-based alternative.

Thoughts?


[1] 
https://github.com/Exiv2/exiv2/commit/67859f4f4ec48301a407410952068333a778fba3
[2] https://bugzilla.gnome.org/show_bug.cgi?id=782449