[plugins] Compile plugins.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
[plugins] jostle.c: change tab with spaces.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
[plugins] Added lockelements.c.

Signed-off-by: bert <bert.timmerman@xs4all.nl>
[plugins] Added polystitch.c.

Signed-off-by: bert <bert.timmerman@xs4all.nl>