Bug: receive config on knob adds additional backslash in escaped spaces

[dromer]

Steps:

create a [knob], add a receive config with spaces. save the patch and close it.
reopen the patch and save it again: extra backslashes are added.

example:

#X obj 110 120 vsl 17 128 0 127 0 0 empty testing\ @hv_param empty 0 -9 0 10 #191919 #ffffff #ffffff 0 1;
#X obj 229 172 knob 50 0 127 0 0 empty testing2\\\ @hv_param #191919 #626262 #FFFFFF 1 0 0 0 1 270 0 0 0 empty empty 0 12 6 -15 0 1 0 0;

I don't think it happens with other objects.

[dromer]

Note:

This probably also happens on the other string inputs for this object.

Also need to double-check all the other GUI objects that support these.