gst-device-monitor: Do not serialize string properties in the output & quote launch string for the current shell
gst-device-monitor: Do not serialize string properties in the output
These properties are supposed to be readable by humans, and extraneous
quoting makes it harder to figure out what the raw string is.
See: #922
gst-device-monitor: Detect the shell and quote launch string
GstValue serialization is not the same as shell quoting, and raw
strings will also not yield a usable launch string. We need to detect
the string and quote the launch string.
Fixes #922
Edited by Nirbheek Chauhan