Swapped out instances of ghostRadio.net since that no longer exists. Minor, but it bugged me.
Fixes #4 - Support for missing data.
Added the ability to skip values in a line series. For missing data, insert an instance of NSNull into the data series. Data points will be connected with a solid line, points with missing data between them will be connected by a dashed line.
Drawing guidelines, and some minor refactoring.

* Storing the chartRange instead of passing it around everywhere.
* Helper method for getting the y-value for a data value.
* Re-enabled multiple series in the test class.
Fixes a bug introduced in b798397

When drawing multiple series, the first point of subsequent series is now rendered correctly.
Drawing of guide lines. Just don't try animating anything.
Fixed a bug with the chart frame constantly resizing on redraw
Clearing of the drawRect each redraw
Beginning work on drawing different line styles.
Drawing of filled lineseries
Added ability to set the fill color of a filled lineSeries
Preventing rendering if the dataprovider is nil
.GitIgnore updates
Added an initWithCoder method for instances of the chart initialized by InterfaceBuilder
Added the ability to override the range setting on a chart
Fixed a bug where changing the dataprovider didn't result in a redraw
Fix for cases where an array in a chart series may have fewer data points than other arrays in the series.
Setting of grid line colors.
Flags to toggle drawing of the different labels.
Adjusting of chartframe based on whether we're drawing labels.
Toggling of dashed grid lines.