Update headings typography.

[betsydupuis]

Here are the properties that are needed. Some properties will need to be overridden, others can be stored in variables. Foundation uses em units instead of pixels, so be mindful to convert these units if the framework doesn't do it already.

.h1 {
	font-weight: bold;
	text-transform: uppercase;
	font-size: 48px;
	line-height: 48px;
	margin-bottom: 24px;
}
.h2 {
	font-weight: normal;
	font-size: 36px;
	line-height: 36px;
	margin-bottom: 12px;
}
.h3 {
	font-weight: bold;
	text-transform: uppercase;
	font-size: 30px;
	line-height: 36px;
	margin-bottom: 12px;
}
.h4 {
	font-weight: normal;
	font-size: 24px;
	line-height: 24px;
	margin-bottom: 12px;
}
.h5 {
	font-weight: normal;
	text-transform: uppercase;
	font-size: 18px;
	line-height: 24px;
	margin-bottom: 12px;
}
.h6 {
	font-weight: normal;
	text-transform: uppercase;
	font-size: 14px;
	line-height: 24px;
	margin-bottom: 12px;
}