Netlist spice creation: fix serious issues.

* fix broken float values in countries using a comma as separator (missing LOCALE_IO switch)
* fix regression that ignored the pseudo directive Kxx Lyy Lzz nn (coupling factor)
* fix regression that created empty blocks for .subckt and .control

eeschema/netlist_exporters/netlist_exporter_spice.cpp

@@ -70,6 +70,8 @@ bool NETLIST_EXPORTER_SPICE::WriteNetlist( const wxString& aOutFileName, unsigne
 
 bool NETLIST_EXPORTER_SPICE::GenerateNetlist( OUTPUTFORMATTER& aFormatter, unsigned aNetlistOptions )
 {
+    LOCALE_IO dummy;
+
     // Cleanup list to avoid duplicate if the netlist exporter is run more than once.
     m_rawIncludes.clear();
 
@@ -182,6 +184,31 @@ void NETLIST_EXPORTER_SPICE::ReadDirectives()
             else
                 continue;
 
+            // Some directives have a plain text inside them:
+            //  .control (that ends with .endc
+            //  .subckt (that ends with .ends
+            // So we insert the full text in netlist without any test
+            // (it is not the right place here to verify the directive)
+            if( text.StartsWith( ".control" ) || text.StartsWith( ".subckt") )
+            {
+                m_directives.emplace_back( text );
+                continue;
+            }
+
+            // A specific "directive" allows entering coupling parameter between 2 inductors
+            // Kxx Lyy Lzz nn (xx, yy, zz are digits, nn is the coupling value
+            if( text.StartsWith( "K" ) )
+            {
+                wxRegEx couplingK( "^[kK][[:digit:]]*[[:space:]]+[[:alnum:]]+[[:space:]]+[[:alnum:]]+",
+                                   wxRE_ADVANCED );
+
+                if( couplingK.Matches( text ) )     // K## L## L## coupling constant
+                {
+                    m_directives.emplace_back( text );
+                    continue;
+                }
+            }
+
             tao::pegtl::string_input<> in( ( text + "\n" ).ToUTF8(), "from_content" );
             std::unique_ptr<tao::pegtl::parse_tree::node> root;
 
@@ -201,7 +228,9 @@ void NETLIST_EXPORTER_SPICE::ReadDirectives()
             for( const auto& node : root->children )
             {
                 if( node->is_type<NETLIST_EXPORTER_SPICE_PARSER::dotTitle>() )
+                {
                     m_title = node->children.at( 0 )->string();
+                }
                 else if( node->is_type<NETLIST_EXPORTER_SPICE_PARSER::dotInclude>() )
                 {
                     wxString path = node->children.at( 0 )->string();
@@ -358,8 +387,6 @@ void NETLIST_EXPORTER_SPICE::readPinNetNames( SCH_SYMBOL& aSymbol, SPICE_ITEM& a
         ReplaceForbiddenChars( netName );
         netName = UnescapeString( netName );
 
-        LOCALE_IO toggle;
-
         if( netName == "" )
             netName = wxString::Format( wxT( "NC-%u" ), aNCCounter++ );