Update Octave manual to use "swigexample" instead of "example"

Closes #46
Guile examples consistency changes

Use new guile_embedded_run target or guile_run target for running the
examples like the other target languages (for suppressing stdout if run
from top level).

Consistency with other target language file renames: use runme.scm for
scripts and example.i, example.c for example code.

Add class example to examples being tested.