bash script improvements

- bash_startup improvements (seeing a performance improvement of about
  36ms in parsing the default.ftcommands, also removes external calls to
  sed)
  - use parameter substitution instead of splitting with the IFS when
    reading default.ftcommands
  - escape quotes using parameter substitution instead of sed
  - replace sed in trim with parameter substitution
Update about dialog credits
Merge branch 'master' of https://github.com/jmittert/finalterm
Update about dialog credits