We used to move the header files in /usr/include/libev, whereas upstream
(and other distributions) put them in /usr/include.
This was confusing users of the library, who had to either come up with
clever tricks to build on Fedora (often as downstream changes to the
packages in Fedora) or worse, depend on the Fedora-only changes, so that
the software would not build anywhere else.
However, this means that the /usr/include/event.h file (which we used to
put in /usr/include/libev/event.h) now conflicts with the one from
libevent-devel.
To avoid making libev-devel conflict with libevent-devel (which would be
pretty terrible for users of both libraries, like the libverto
developers for example), this commit introduces a new
libev-libevent-devel subpackage just to contain this one header file, so
that only this subpackage conflicts with libevent-devel.
Given that the point of libev's event.h was to be a compatibility header
with libevent, this actually makes it easier for users to rely on it.
Finally, the pkgconfig file becomes completely unnecessary. As it was a
Fedora-specific change that libev upstream rejected several times when
it was proposed to them, this commit also drops it.
All in all, this should remove user confusion over the Fedora libev
package, and stop various upstreams from depending on Fedora-specific
changes.
Note that this should really not be pushed in Fedora <= 20 at this time,
but only to Rawhide.
