grammar.py: Add support for --irrelevant-symbols

Arguments to --irrelevant-symbols are not meant to be represented in the
AST resulting from parsing.

Also, add pad() to misc.py.

Signed-off-by: Jan Lindemann <jan@janware.com>

tools/python/jwutils/log.py

@@ -3,6 +3,7 @@ import syslog
 import sys
 import inspect
 from os.path import basename
+import misc
 
 EMERG = syslog.LOG_EMERG
 ALERT = syslog.LOG_ALERT
@@ -63,15 +64,6 @@ prio_colors = {
     EMERG   : [ CONSOLE_FONT_BOLD + CONSOLE_FONT_MAGENTA, CONSOLE_FONT_OFF ],
 }
 
-def __pad(token, total_size, right_align = False):
-    add = total_size - len(token)
-    if add <= 0:
-        return token
-    space = ' ' * add
-    if right_align:
-        return space + token
-    return token + space
-
 def get_caller_pos(up = 1):
     assert(up == 1) # TODO: implement this
     caller_frame = inspect.currentframe().f_back.f_back
@@ -95,7 +87,7 @@ def slog(prio, *args, **kwargs): # export
             name, line = kwargs['caller']
         else:
             name, line = get_caller_pos(1)
-        msg += __pad(name, 20) + '[' + __pad(str(line), 4, True) + ']'
+        msg += misc.pad(name, 20) + '[' + misc.pad(str(line), 4, True) + ']'
 
     if f_color in flags:
         color_on, color_off = prio_colors[prio]