Add a special case of transport_compose

This way, [SearchAbout transport idmap.] gives something sensical.

This closes #211.
Uniformize the order of [Set]s at the top of files
Merge pull request #250 from JasonGross/transport-idmap-ap

Add a special case of transport_compose
Merge pull request #252 from JasonGross/uniformize-set

Uniformize the order of [Set]s at the top of files
Update .gitignore with some more files