Merge branch '4270_cleanup'

Merge branch '4270_cleanup'

* 4270_cleanup: (33 commits)
  Upate po/*.po files.
  mc.lib: move xterm alt-shift-arrow definitions to lib/tty/key.c.
  mc.lib: [terminal:linux] is same as [terminal:console].
  (delete_region, copy_region): rename arguments.
  src/editor/editwidget.c: grammar.
  mceditor: use MB_LEN_MAX constant.
  (string_file_name): use mc_g_string_copy.
  (complete_engine, insert_text): don't calculate text length twice.
  lib/strutil/strutilutf8.c: use MB_LEN_MAX constant.
  Remove get_process_stats() test.
  Use g_get_monotonic_time() instead of g_get_real_time().
  (learn_key): return NULL if buffer is empty.
  (learn_key): use g_get_real_time () to simplify time comparision.
  (get_key_code): use g_get_real_time () to simplify time comparision.
  (xmouse_get_event): use g_get_real_time () to simplify time comparision.
  lib/tty/key.c: use named constants for time intervals.
  (file_mask_dialog): indentation.
  Reimplement compiler options checking.
  lib/util.c: remove unneeded include.
  lib/keybind.h: remove unneeded includes.
  ...