Further polish SQLite vendoring

- Now integrated with `make tags` for Emacs IDE features
- Delete some old deprecated broken full-text search engines
- Rename .h → .inc files that don't meet our definition of header
- Make sure every #include line is normal form so tools understand

See #162

third_party/sqlite3/fts3_unicode.c

@@ -16,14 +16,14 @@
 
 #ifndef SQLITE_DISABLE_FTS3_UNICODE
 
-#include "third_party/sqlite3/fts3Int.h"
+#include "third_party/sqlite3/fts3Int.inc"
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
 #include "libc/assert.h"
 #include "libc/mem/mem.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
-#include "third_party/sqlite3/fts3_tokenizer.h"
+#include "third_party/sqlite3/fts3_tokenizer.inc"
 
 /*
 ** The following two macros - READ_UTF8 and WRITE_UTF8 - have been copied