native tooltip bugfixes & small cosmetic fixes

Some small bugfixes in the new tooltips:

 - in temp basal tooltips, the u/hr in the description of the scheduled rate was too large
 - there wasn't enough space in the title when 'INTERRUPTED' was there
 - there was very little space between 'Delivered' and the value for a quick correction bolus (i.e., nothing else in the tooltip except the delivery amount)

Also some cosmetic fixes requested by @skrugman:

 - removed parens and switched from U to u for units
 - lighter weight fonts in pool labels (NB: not reflected in tideline example)

All this is low risk, will merge to master soon and deploy to devel.