apps/interpreters/minibasic:  Add a port of Mini Basic, version 1.0, written by Malcom McLean and released under the Creative Commons Attirbution license.

Add the dirlinks target to some Makefiles.  This plugs some wholes open by last chicken-and-egg build fix

apps/canutils/libcanard: Update version

(1) Make.defs set the include path in CFLAGS, but not in CXXFLAGS, (2) canutils/libuavcan/Makefile should not use explication / delimiters.  It should not use -I.  I should use DELIM: command not found and nuttx/tools/incdir.sh

apps/examples/pty_test: If CONFIG_SERIAL_TERMIOS is not selected, then don't call tcgetattr or tcsetattr.

minor; media app is intended to take either a command line argument, or a compiled-in default value from config.  However, the default is ignored, leading to confusing error messages.

minor; media app is intended to take either a command line argument, or a compiled-in default value from config.  However, the default is ignored, leading to confusing error messages.

apps/examples/pty_test:  Use of POLL must be optional. There are still a few character drivers that do not support it.