Merge pull request #101 from bluss/inline-constructors

Mark some distribution constructors #[inline]
diff --git a/src/distributions/exponential.rs b/src/distributions/exponential.rs
index 9449fc6..ddf5543 100644
--- a/src/distributions/exponential.rs
+++ b/src/distributions/exponential.rs
@@ -80,6 +80,7 @@
 impl Exp {
     /// Construct a new `Exp` with the given shape parameter
     /// `lambda`. Panics if `lambda <= 0`.
+    #[inline]
     pub fn new(lambda: f64) -> Exp {
         assert!(lambda > 0.0, "Exp::new called with `lambda` <= 0");
         Exp { lambda_inverse: 1.0 / lambda }
diff --git a/src/distributions/gamma.rs b/src/distributions/gamma.rs
index 6d01dc2..e890bf4 100644
--- a/src/distributions/gamma.rs
+++ b/src/distributions/gamma.rs
@@ -97,6 +97,7 @@
     /// distribution.
     ///
     /// Panics if `shape <= 0` or `scale <= 0`.
+    #[inline]
     pub fn new(shape: f64, scale: f64) -> Gamma {
         assert!(shape > 0.0, "Gamma::new called with shape <= 0");
         assert!(scale > 0.0, "Gamma::new called with scale <= 0");
diff --git a/src/distributions/normal.rs b/src/distributions/normal.rs
index e140323..711995f 100644
--- a/src/distributions/normal.rs
+++ b/src/distributions/normal.rs
@@ -101,6 +101,7 @@
     /// # Panics
     ///
     /// Panics if `std_dev < 0`.
+    #[inline]
     pub fn new(mean: f64, std_dev: f64) -> Normal {
         assert!(std_dev >= 0.0, "Normal::new called with `std_dev` < 0");
         Normal {
@@ -147,6 +148,7 @@
     /// # Panics
     ///
     /// Panics if `std_dev < 0`.
+    #[inline]
     pub fn new(mean: f64, std_dev: f64) -> LogNormal {
         assert!(std_dev >= 0.0, "LogNormal::new called with `std_dev` < 0");
         LogNormal { norm: Normal::new(mean, std_dev) }