This allows us to a) move away from cairo's "toy" API, and b) let the
user specify font options in a single font "name" string:
Serif:size=10:weight=bold:slant=italic
This also allows us to simplify the font code significantly (except
for the fontconfig parts...); the font no longer sets itself in a
cairo surface - font users do that; the font simply returns a
cairo_scaled_font_t.
Furthermore, font_clone() has now been simplified to basically just
refcount the scaled font. I.e. there's no need to run the full
constructor and lookup and instantiate the cairo scaled font again.
State exposed (tag names):
* name: the interface name ("eth0" etc)
* index: the interface index, "ifindex"
* state: operational state (down, up etc)
* mac: the Ethernet hardware address
* ipv4: the *last* IPv4 address added to the interface
* ipv6: the *last* IPv6 address added to the interface
State we monitor (for changes):
* state
* ipv4 addresses
* ipv6 addresses
This allows us to detect plug/unplug events immediately, instead of
having to wait for the next poll event.
Unfortunately, capacity changes do not appear to generate events :(
The ramp particle is configured with a tag name and a list of
particles.
At instantiation time, a single particle is selected from the list,
depending on the tag value and it's minimum and maximum values.
I.e. this particle acts kind of like a progress bar.