Mark SafeHandle interop constructors private

src/TensorFlowNET.Core/Eager/SafeContextHandle.cs

@@ -21,7 +21,7 @@ namespace Tensorflow.Eager
 {
     public sealed class SafeContextHandle : SafeTensorflowHandle
     {
-        public SafeContextHandle()
+        private SafeContextHandle()
         {
         }
 

src/TensorFlowNET.Core/Eager/SafeContextOptionsHandle.cs

@@ -21,7 +21,7 @@ namespace Tensorflow.Eager
 {
     public sealed class SafeContextOptionsHandle : SafeTensorflowHandle
     {
-        public SafeContextOptionsHandle()
+        private SafeContextOptionsHandle()
         {
         }
 

src/TensorFlowNET.Core/Graphs/SafeImportGraphDefOptionsHandle.cs

@@ -21,7 +21,7 @@ namespace Tensorflow
 {
     public sealed class SafeImportGraphDefOptionsHandle : SafeTensorflowHandle
     {
-        public SafeImportGraphDefOptionsHandle()
+        private SafeImportGraphDefOptionsHandle()
         {
         }
 

src/TensorFlowNET.Core/Sessions/SafeSessionOptionsHandle.cs

@@ -21,7 +21,7 @@ namespace Tensorflow
 {
     public sealed class SafeSessionOptionsHandle : SafeTensorflowHandle
     {
-        public SafeSessionOptionsHandle()
+        private SafeSessionOptionsHandle()
         {
         }
 

src/TensorFlowNET.Core/Status/SafeStatusHandle.cs

@@ -21,7 +21,7 @@ namespace Tensorflow
 {
     public sealed class SafeStatusHandle : SafeTensorflowHandle
     {
-        public SafeStatusHandle()
+        private SafeStatusHandle()
         {
         }