Display percentage outside for slices that are too small

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Situation:
A pie chart has slices that are so small that the percentage label is clipped 
inside its slice.

Version information:
pgf-pie 2011/10/02 v0.2

Steps to reproduce:
- Radius 2
- Slice 2% and slice 98%
- Percentage label inside 2% slice is clipped.

Reproducibility:
100%

Expected behaviour:
Precentage is displayed outside of the slice.

Actual behaviour:
Percentage label inside slice is clipped.

Suggested solutions:
Variant a)
If possible automatically detect clipping and ad percentage to the outside 
label instead of inside the slice.
Variant b)
Add user option for minimum slice percentage. All percentages below this 
minimum are displayed outside of the pie chart.

Attachments:
Added a sample where the small slice is black to hide the fact that the 
percentage is clipped and the percentage was added to the label outside the pie.

Original issue reported on code.google.com by [email protected] on 22 Jan 2012 at 10:09

Attachments:

• Slice_percentage_label_outside_pie.png