Improve generating wxSTC code and documentation

Several new features were implemented in gen_iface.py and accompanying '.in' files:
1. Added an option to parse provisional section in Scintilla.iface. When global variable GENERATE_PROVISIONAL_ITEMS is set to 1, methods and values in this section receive corresponding wxSTC items.
2. Deprecated section in Scintilla.iface is not skipped, but parsed and corresponding wxSTC items are created (marked as deprecated in the code and documentation).
3. Added a set 'notMappedSciValues' that can be used to prevent the creation of specific wxSTC values which are intended to be handled manually.
4. For deprecated constants there is generated a code to raise respective warnings during the compilation.

Closes #17671.

interface/wx/stc/stc.h

@@ -164,10 +164,6 @@
 #define wxSTC_INDIC_IME_MAX 35
 #define wxSTC_INDIC_MAX 35
 #define wxSTC_INDIC_CONTAINER 8
-#define wxSTC_INDIC0_MASK 0x20
-#define wxSTC_INDIC1_MASK 0x40
-#define wxSTC_INDIC2_MASK 0x80
-#define wxSTC_INDICS_MASK 0xE0
 #define wxSTC_INDICVALUEBIT 0x1000000
 #define wxSTC_INDICVALUEMASK 0xFFFFFF
 #define wxSTC_INDICFLAG_VALUEFORE 1
@@ -329,8 +325,6 @@
 #define wxSTC_VS_NOWRAPLINESTART 4
 #define wxSTC_TECHNOLOGY_DEFAULT 0
 #define wxSTC_TECHNOLOGY_DIRECTWRITE 1
-#define wxSTC_TECHNOLOGY_DIRECTWRITERETAIN 2
-#define wxSTC_TECHNOLOGY_DIRECTWRITEDC 3
 
 /// Line end types which may be used in addition to LF, CR, and CRLF
 /// SC_LINE_END_TYPE_UNICODE includes U+2028 Line Separator,
@@ -2428,6 +2422,22 @@
 
 //}}}
 
+
+//The following values are deprecated in the Scintilla library
+
+///@deprecated
+#define wxSTC_INDIC0_MASK 0x20
+
+///@deprecated
+#define wxSTC_INDIC1_MASK 0x40
+
+///@deprecated
+#define wxSTC_INDIC2_MASK 0x80
+
+///@deprecated
+#define wxSTC_INDICS_MASK 0xE0
+
+
 // Commands that can be bound to keystrokes {{{
 
 
@@ -4317,9 +4327,8 @@ public:
 
     /**
         Set the current styling position to start.
-        The unused parameter is no longer used and should be set to 0.
     */
-    void StartStyling(int start, int unused=0);
+    void StartStyling(int start);
 
     /**
         Change style from current styling position for length characters to a style