Made logger constructor take a std::string instead of char*

dlib/logger/logger_kernel_1.cpp

@@ -432,7 +432,7 @@ namespace dlib
 
     logger::
     logger (  
-        const char* name_
+        const std::string& name_
     ) : 
         gd(get_global_data()),
         logger_name(name_),

dlib/logger/logger_kernel_1.h

@@ -227,7 +227,7 @@ namespace dlib
                                         const uint64, const char*> hook_mfp;
 
         logger (  
-            const char* name_
+            const std::string& name_
         );
 
         virtual ~logger (

dlib/logger/logger_kernel_abstract.h

@@ -211,7 +211,7 @@ namespace dlib
     public:
 
         logger (  
-            const char* name_
+            const std::string& name_
         );
         /*!
             requires