Slightly update font styling

[aljelly]

This is the same mockup picture from the time/date issue, but whilst I was doing that I used the GDK inspector to edit the font sizes (again, ignore the "Something" entry in the mock up).

Before (what it currently looks like):

After (mockup):

• Writing font changed to size 10
• Removed ":" from the Notebook name at the bottom (actually, this is for the "x Pages", it doesn't show in Edit mode)
• CSS used in Introspector:

List Header

.h3.label {
	font-size:1em;
	padding-top:2px;
}

Description label:

.label.dim-label {
	font-size:1em;
	opacity:0.9;
}

Date/time label (see #257):

.label.would-be-datetime-label {
	font-size:0.9em;
	padding-bottom:2px;
	opacity:0.6;
}

Also: currently if a note only has a title (in other words only the first line has text), the empty dim-label is still there and consumes space (creating a gap). You could probably just hide the dim-label when it's empty.

[Philip-Scott]

Hmmm i like it. It would be a good change :) Do you want to be the one who makes the change in code?