Simple fixes/optimization of things discovered during review of new pushed code


include/my_sys.h:
  Ensure that clear_alloc_root() interacts correctly with alloc_root_inited()
mysys/hash.c:
  More comments
  Simple optimization (merge identical code)
mysys/my_bitmap.c:
  Change inline -> static inline
sql/examples/ha_archive.cc:
  Fixed compiler warning
sql/ha_ndbcluster.cc:
  true,false -> TRUE, FALSE
  Change if (false) -> #ifdef NOT_USED
sql/ha_ndbcluster.h:
  true,false -> TRUE, FALSE
sql/handler.cc:
  More comments
  Remove not needed initializations.
  #ifdef not used code
sql/item_cmpfunc.h:
  true,false -> TRUE, FALSE
sql/item_strfunc.cc:
  Move local variables to function beginning
  Remove wrong comments
sql/log_event.h:
  true,false -> TRUE, FALSE
sql/sql_base.cc:
  true,false -> TRUE, FALSE
  More comments
sql/sql_help.cc:
  true,false -> TRUE, FALSE
sql/sql_lex.cc:
  Simple optimization of new code
sql/sql_parse.cc:
  true,false -> TRUE, FALSE
sql/sql_prepare.cc:
  true,false -> TRUE, FALSE
sql/sql_table.cc:
  true,false -> TRUE, FALSE
sql/sql_yacc.yy:
  true,false -> TRUE, FALSE