SelfLog full exception info

In some places only the exception message was written to SelfLog which is not sufficient. Use Exception.ToString() for all exceptions which this sink logs to Serilog SelfLog. ToString() adds exception type, message, call stack, inner exceptsions, etc.

Fixes issue #432.

src/Serilog.Sinks.MSSqlServer/Sinks/MSSqlServer/Platform/SqlBulkBatchWriter.cs

@@ -56,7 +56,8 @@ public async Task WriteBatch(IEnumerable<LogEvent> events, DataTable dataTable)
             }
             catch (Exception ex)
             {
-                SelfLog.WriteLine("Unable to write {0} log events to the database due to following error: {1}", events.Count(), ex.Message);
+                SelfLog.WriteLine("Unable to write batch of {0} log events to the database due to following error: {1}",
+                    events.Count(), ex);
             }
             finally
             {

src/Serilog.Sinks.MSSqlServer/Sinks/MSSqlServer/Platform/SqlLogEventWriter.cs

@@ -70,7 +70,7 @@ public void WriteEvent(LogEvent logEvent)
             }
             catch (Exception ex)
             {
-                SelfLog.WriteLine("Unable to write log event to the database due to following error: {0}", ex.Message);
+                SelfLog.WriteLine("Unable to write log event to the database due to following error: {0}", ex);
                 throw;
             }
         }

src/Serilog.Sinks.MSSqlServer/Sinks/MSSqlServer/Platform/SqlTableCreator.cs

@@ -42,7 +42,7 @@ public void CreateTable(DataTable dataTable)
             }
             catch (Exception ex)
             {
-                SelfLog.WriteLine("Exception creating table {0}:\n{1}", _tableName, ex.ToString());
+                SelfLog.WriteLine("Unable to create database table {0} due to following error: {1}", _tableName, ex);
             }
         }
     }