add evaler

README.md

@@ -561,6 +561,7 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
 
 * [blas](https://github.com/ziutek/blas) - Implementation of BLAS (Basic Linear Algebra Subprograms)
 * [chart](https://github.com/vdobler/chart) - Simple Chart Plotting library for Go. Supports many graphs types.
+* [evaler](https://github.com/soniah/evaler) - A simple floating point arithmetic expression evaluator
 * [ewma](https://github.com/VividCortex/ewma) - Exponentially-weighted moving averages
 * [geom](https://github.com/skelterjohn/geom) - 2D geometry for golang
 * [go-fn](https://code.google.com/p/go-fn/) - Mathematical functions written in Go language, that are not covered by math pkg