Add erasure coding and decoding using Intel Storage Acceleration library

- move contrib/erasure --> contrib/isal
 - bring in low level 'isal' package for Go for exposing C functions
 - Implement Erasure 'encoding'
   Supports - Reed Solomon Codes, Cauchy Codes
 - Implement Erasure 'decoding'
   Supports - Reed Solomon Codes, Cauchy Codes
 - Renames Minios -> Minio at all the references

erasure/ctypes.go

@@ -0,0 +1,58 @@
+/*
+ * Mini Object Storage, (C) 2014 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package erasure
+
+import "C"
+import (
+	"fmt"
+	"unsafe"
+)
+
+// Integer to Int conversion
+func Int2cInt(src_err_list []int) *C.int {
+	SrcErrInt := int(unsafe.Sizeof(src_err_list[0]))
+	switch SrcErrInt {
+	case SizeInt:
+		return (*C.int)(unsafe.Pointer(&src_err_list[0]))
+	case SizeInt8:
+		Int8Array := make([]int8, len(src_err_list))
+		for i, v := range src_err_list {
+			Int8Array[i] = int8(v)
+		}
+		return (*C.int)(unsafe.Pointer(&Int8Array[0]))
+	case SizeInt16:
+		Int16Array := make([]int16, len(src_err_list))
+		for i, v := range src_err_list {
+			Int16Array[i] = int16(v)
+		}
+		return (*C.int)(unsafe.Pointer(&Int16Array[0]))
+	case SizeInt32:
+		Int32Array := make([]int32, len(src_err_list))
+		for i, v := range src_err_list {
+			Int32Array[i] = int32(v)
+		}
+		return (*C.int)(unsafe.Pointer(&Int32Array[0]))
+	case SizeInt64:
+		Int64Array := make([]int64, len(src_err_list))
+		for i, v := range src_err_list {
+			Int64Array[i] = int64(v)
+		}
+		return (*C.int)(unsafe.Pointer(&Int64Array[0]))
+	default:
+		panic(fmt.Sprintf("Unsupported: %d", SizeInt))
+	}
+}