perfetto_cmd: Improve --query user-friendliness
perfetto_cmd: Improve --query user-friendliness

- If the command is ran as shell (vs root) traced will report only
  tracing sessions owned by shell. This is fine but can be surprising.
  When this happens add an explicit message to explain.

- Reorder some columns. Sessions names can be long and break the
  column layout.

Test: manual: `./perfetto --query` vs `su root ./perfetto --query`
Change-Id: I2d93d0a2bc4d804d1480041d9c883c51f61d5780
google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto