Replace the stylesheet hack with inline styles.

The purpose of the stylesheet hack was to provide a default without
having to use inline styles on containers.  We can do this much more
neatly by instead just giving the inline styles to a parent container,
leaving users free to customize the children.
A better fix for the font-size 'smaller' problem.

This resolves #991, replacing the earlier temporary patch.  It takes
advantage of the fact that line-height can take the form of a unit-less
integer, in which case it mirrors the font-size, even when it is
something abstract, like 'smaller'.  We can then read the dummy
element's height to learn the effective font-size.
Move time-specific options into the time plugin.
Fix incorrect default for xaxes/yaxes tickColor.

The way in which xaxes/yaxes inherit options from xaxis/yaxis resulted
in a minor bug, where tickColor defaulted to the xaxis/yaxis color
instead of the color for its axis.  Fixed by applying the default before
extending the per-axis options, resolving #984.

There's still some questionable behavior here; this section should be
revisited for 0.9, especially with an eye towards removing some of the
code that only exists for backwards-compatibility.
Merge pull request #1 from flot/master

Update from upstream/master