Calendar entry customization

[jonfawcett]

create setting field to customize the calendar entry. Idea:

Variables wrapped in % that get replaced in code by the up to date text.
%BG%
%DELTA%
%DIRECTION%
%MINAGO%
%LOOPSTATUS%
%COB%
%IOB%
%BASAL%

Example Line 1: "%BG% %DIRECTION% %DELTA% %MINAGO%min"
Example Line 2: "C:%COB% I:%IOB B:%BASAL"

[jonfawcett]

added main ones. Need to add Loop status, pump, battery, override, prediction