Consider 'provides' field when quering dependant packages

[f2404]

Looks like this is required in order to resolve yaourt issue: archlinuxfr/yaourt#39

[f2404]

The original issue has been resolved within yaourt.

However, do we want to show the packages depending on the provided items, as well as depending on the target itself?

For example, currently the output is

$ package-query -S --qdepends vid.stab
community/openshot 1.4.3-5

And it could be changed to also consider libvidstab.so=1.1-32 which is provided by vid.stab; so the output would be something like

$ package-query -S --qdepends vid.stab
community/openshot 1.4.3-5
extra/ffmpeg 1:2.8.1-3 [installed] [depends on libvidstab.so=1.1-32]

[Skunnyk]

Yup, You can implement this !