Added selection plugin options.

Tweaked the description to indicate that we no longer combine single
slices into 'other', and reduced the threshold from 10% to 5% to
encourage more slices to combine in the demo.

Resolves #638.

Resolves #489.

Previously, the minimum size a selection could be was set at five
pixels. This commit adds the ability to customize this value.

Previously, if the selected area was very small, the selection
rectangle would not be displayed. This commit adds an "alwaysShow"
option so that, when true, the selection rectangle will always be
displayed. When the selected area is very small, the selection
rectangle will become a line.

This commit adds an option for the shape of the corners of the
selection rectangle. By default the shape is set to "round" (the
previous setting for lineJoin). The other options are "bevel" and
"miter".

This resolves issue #964.

Fix example (syntax error and indenting).

Add basic Travis CI setup with test script that runs JSHint.

This resolves #18, but without catching zero, which is a valid key.

Added a legend 'reverse' sorting option.

This orders the legend entries in reverse order of their series.

Added the plot function as a chainable property.

Modern browser consoles obviate the need for an object logging function.

The previous processing step already guarantees that the values are
numeric.

This resolves #534 by handling the case where data is a string, whether
it is provided alone or as a pair.  We can also eliminate the old and
unnecessary check for undefined values.

Resolves #734 and #816.

Fix inability to set the point lineWidth to 0.

This resolves #895.

This temporary fix addresses the problem described in #810, and possibly
#945, where calls to setData for a pie chart do nothing.