ps/tmp/isolate should be filtered from `gps ls`

[Alizter]

When there are issues isolating, the ps/tmp/isolate branch gets left over. This shows up in the output of gps ls:

10   e0f75a4 get rid of isgraph_arrow                           ( ps/rr/get_rid_of_isgraph_arrow l*r* ps/tmp/isolate l* ) 
11   4e847b4 shorten terms in Group.v                           ()

[drewdeponte]

We probably should filter ps/tmp/isolate out of the branches in the gps ls command because it is a special temporary branch used behind the scenes and doesn't conceptually map to a formal patch series.

[Alizter]

Is ps/tmp/isolate being leftover the correct behaviour? If not, then simply making sure it is cleaned up would also work.