Exports should include friendly names

[MisterPhilip]

Currently the export feature just exports the raw URL/POST data and it does not break values out into separate columns like the interface does. This should be updated to include the separate columns as shown in the interface.

Decision points that'll need to be made for this:

• Do we show...
  • Omnibug-provided column names
  • User-provided column names (e.g. changing eVar3 to Page Type)
• For column names, do we...
  • Combine the same column names (e.g. Page URL) for all providers when they have different parameter keys? This would require more work to ensure that the names we use are consistent (which we should be doing anyways) but also unique enough that we aren't combining things that shouldn't be.
  • Combine the same column names (e.g. Page URL) only when they have the same parameter key (e.g. pageurl)
  • Break out each provider into their own columns