Missing avi demuxer

[bielski at fastmail.net]

Ok, I've found a solution. 
After the previous step gst-launch-1.0 works good but openCV still
doesn't work (probably it uses 0.10 version instead of 1.0), so:
1)
I deleted gst-launch, gst-typefind and gst-inspect (that was copies of
gst-launch-0.10 and so forth...) from /usr/bin and /usr/local/bin,
2)
Made the new versions of those files as copies of gst-launch-1.0 etc.
int both locations,
3)
set environmental variable, i.e inside .bash_profile:
GST_PLUGIN_PATH=/usr/lib64/gstreamer-1.0
export GST_PLUGIN_PATH
4)restart bash (or make . ~/.bash_profile) to apply changes

Then it works...

P.S. This is only for your information, maybe you will decide to publish
that issue somewhere so I wanted to let you know my solution.