Handle boluses with an unknown split

This change adjust the bolus rendering code to be able to handle boluses with an unknown immediate and extended split.  To get diasend data working properly though, it requires the diasend data to be adjusted some, which is currently being done in blip.  Without the blip changes, the rendering will remain the same, with the blip changes, diasend square basals will have a duration line on them.
rename some things to match tideline naming
add styling for unknown delivery split extended boluses
edit an extended bolus to have an unknown delivery split
Avoid truthyness
adjust tooltip text getters; use 'datum' everywhere instead of 'd' when not a proper D3 selection to avoid confusion
Merge pull request #80 from tidepool-org/cheddar/fix-boluses-with-unknown-split-63

Handle boluses with an unknown split