format SafeMath documentation as NatSpec

contracts/math/SafeMath.sol

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+pragma solidity ^0.4.11;
+
+
+/**
+ * @title SafeMath
+ * @dev Math operations with safety checks that throw on error
+ */
+library SafeMath {
+  function mul(uint256 a, uint256 b) internal returns (uint256) {
+    uint256 c = a * b;
+    assert(a == 0 || c / a == b);
+    return c;
+  }
+
+  function div(uint256 a, uint256 b) internal returns (uint256) {
+    // assert(b > 0); // Solidity automatically throws when dividing by 0
+    uint256 c = a / b;
+    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
+    return c;
+  }
+
+  function sub(uint256 a, uint256 b) internal returns (uint256) {
+    assert(b <= a);
+    return a - b;
+  }
+
+  function add(uint256 a, uint256 b) internal returns (uint256) {
+    uint256 c = a + b;
+    assert(c >= a);
+    return c;
+  }
+
+  function max64(uint64 a, uint64 b) internal constant returns (uint64) {
+    return a >= b ? a : b;
+  }
+
+  function min64(uint64 a, uint64 b) internal constant returns (uint64) {
+    return a < b ? a : b;
+  }
+
+  function max256(uint256 a, uint256 b) internal constant returns (uint256) {
+    return a >= b ? a : b;
+  }
+
+  function min256(uint256 a, uint256 b) internal constant returns (uint256) {
+    return a < b ? a : b;
+  }
+
+}