Ignored the unused methods in system class templates.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/Generator/Passes/IgnoreSystemDeclarationsPass.cs

@@ -51,6 +51,8 @@ namespace CppSharp.Passes
             switch (@class.Name)
             {
                 case "basic_string":
+                    foreach (var method in @class.Methods.Where(m => m.OriginalName != "c_str"))
+                        method.ExplicitlyIgnore();
                     foreach (var specialization in @class.Specializations.Where(s => !s.Ignore))
                     {
                         foreach (var method in specialization.Methods.Where(m => m.OriginalName != "c_str"))
@@ -62,10 +64,32 @@ namespace CppSharp.Passes
                         foreach (var parameter in ctor.Parameters)
                             parameter.DefaultArgument = null;
                     }
+                    foreach (var ctor in @class.Methods.Where(m =>
+                        {
+                            if (!m.IsConstructor || m.Parameters.Count != 2)
+                                return false;
+                            for (int i = 0; i < m.Parameters.Count; i++)
+                            {
+                                var type = m.Parameters[i].Type.Desugar();
+                                var templateParameter = (type.GetFinalPointee() ?? type) as TemplateParameterType;
+                                if (templateParameter == null ||
+                                    @class.TemplateParameters.All(t => t.Name != templateParameter.Parameter.Name))
+                                    return false;
+                            }
+                            return true;
+                        }))
+                    {
+                        ctor.GenerationKind = GenerationKind.Generate;
+                        foreach (var parameter in ctor.Parameters)
+                            parameter.DefaultArgument = null;
+                    }
                     break;
                 case "allocator":
-                    foreach (var specialization in @class.Specializations.Where(s => !s.Ignore))
+                    foreach (var method in @class.Methods.Where(m => !m.IsConstructor || m.Parameters.Any()))
-                        foreach (var method in specialization.Methods.Where(m => !m.IsConstructor || m.Parameters.Any()))
+                        method.ExplicitlyIgnore();
+                    foreach (var specialization in @class.Specializations)
+                        foreach (var method in specialization.Methods.Where(
+                            m => !m.IsConstructor || m.Parameters.Any()))
                             method.ExplicitlyIgnore();
                     break;
             }