add contrib list

Readme.md

@@ -250,6 +250,40 @@ Tested with and designed for:
 For node 0.2.x `node-canvas` <= 0.4.3 may be used,
 0.5.0 and above are designed for node 0.4.x only.
 
+## Contributors
+
+```
+project  : node-canvas
+ repo age : 1 year, 11 months
+ active   : 120 days
+ commits  : 963
+ files    : 72
+ authors  : 
+   816	Tj Holowaychuk          84.7%
+    58	TJ Holowaychuk          6.0%
+    23	c-spencer               2.4%
+    16	Nathan Rajlich          1.7%
+    12	atomizer                1.2%
+     6	Elijah Hamovitz         0.6%
+     5	Luigi Pinca             0.5%
+     5	Robert Sköld            0.5%
+     4	obarthel                0.4%
+     3	Don Park                0.3%
+     2	Andreas Botsikas        0.2%
+     2	Gabriel Falcao          0.2%
+     1	Brian McKinney          0.1%
+     1	Seiya Konno             0.1%
+     1	Syoyo Fujita            0.1%
+     1	Marcello Bastea-Forte   0.1%
+     1	Tharit                  0.1%
+     1	Konstantin Käfer        0.1%
+     1	Tom Carden              0.1%
+     1	Walt Lin                0.1%
+     1	David Björklund         0.1%
+     1	Brian White             0.1%
+     1	Philippe Plantier       0.1%
+```
+
 ## License
 
 (The MIT License)