Merge branch '3641_cleanup'
* 3641_cleanup:
lib/mcconfig/paths.c: reduce scope of 'homedir' var.
lib/mcconfig/paths.c: cleanup.
doc/man/mc.1.in: fix substitution markers.
src/vfs/fish/fish.c: apply coding guidelines.
More use link_isdir().
Get rid of #define const_cast().
Fix typos.
Define NCURSES_CONST if curses library doesn't define it.
(ftpfs_open_data_connection): fix enable/disable interrupt key.
(ftpfs_open_data_connection): fix socket leak in case of unsuccessful ftp connection.
(dlg_adjust_position): refactoring.
Ticket #3641: code cleanup before 4.8.18 release.