Rename header files.

src/lexer.c

@@ -1,6 +1,6 @@
 #include "lexer.h"
 #include "ll.h"
-#include "libabacus_util.h"
+#include "util.h"
 #include <stdlib.h>
 #include <ctype.h>
 

src/parser.c

@@ -1,6 +1,6 @@
 #include "parser.h"
-#include "libabacus_util.h"
-#include "libabacus_result.h"
+#include "util.h"
+#include "result.h"
 #include "lexer.h"
 #include <stdlib.h>
 #include <string.h>

src/util.c

@@ -1,4 +1,4 @@
-#include "libabacus_util.h"
+#include "util.h"
 
 libab_result libab_convert_lex_result(liblex_result to_convert) {
     libab_result result = LIBAB_SUCCESS;