animateMotion calcMode defaults to 'paced' timing
Merge pull request #78 from ewilligers/calcMode-defaults-to-paced

animateMotion calcMode defaults to 'paced' timing
Support to-animation where from value is implicitly the current value

to animation is described in
http://www.w3.org/TR/2001/REC-smil-animation-20010904/#AnimFuncValues
"the animation function is defined to start with the underlying value for the attribute, and finish with the value specified with the to attribute. Using this form, an author can describe an animation that will start with any current value for the attribute, and will end up at the desired to value."

Also correct test animateMotion-paced test to use correct element names.
Merge pull request #79 from ewilligers/to-animation

Support to-animation where from value is implicitly the current value
Hyphens and periods in ids can be escaped

The begin and end attributes of SMIL animation elements can refer to other elements by id. They can also contain hyphens and periods with specific meanings: a hyphen for negative offsets, and a period before an event name.

When an element id contains a hyphen or period, that character must be
escaped using a backslash.

http://www.w3.org/TR/SMIL3/smil-timing.html#q21
Merge pull request #80 from ewilligers/escaped-hyphen

Hyphens and periods in ids can be escaped
Improve clarity of animateMotion-paced test

We test for exactly the same behavior if the animation is 'calcMode=paced' explicitly, as we do if calcMode is not specified and so the animation is paced implicitly.
Merge pull request #81 from ewilligers/repeat-animateMotion-paced

Improve clarity of animateMotion-paced test
Fall back to fillDefault when fill is not supplied

fillDefault is defined in
http://www.w3.org/TR/SMIL2/smil-timing.html#adef-fillDefault

When we read the element attributes, 'fillDefault' is exposed by Chrome
as 'filldefault' (no caps)

When fill is 'default' or not supplied, we fall back to using the
(possibly inherited) fillDefault value.
Merge pull request #82 from ewilligers/filldefault-inherited

Fall back to fillDefault when fill is not supplied
Support keyTimes in Motion path animations

keyTimes is mentioned in
http://www.w3.org/TR/SVG/animate.html#KeyPointsAttribute
and defined in
http://www.w3.org/TR/SVG/animate.html#KeyTimesAttribute