Add new dispatch period output for manual dispatch

[brtietz]

New variable "Battery manual dispatch period in this timestep" should appear for manual dispatch (both front of meter and behind the meter) but not for other dispatch modes.

Chose to do a lifetime variable instead of year 1 since I think we're trying to move in that direction.

Fixes #1230

[coveralls]

Pull Request Test Coverage Report for Build 13864218817

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 156 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.002%) to 50.427%

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Files with Coverage Reduction	New Missed Lines	%
ssc/shared/lib_battery_dispatch.h	1	70.59%
ssc/shared/lib_battery_dispatch_manual.cpp	8	87.14%
ssc/ssc/cmod_battery.cpp	147	79.48%

Totals
Change from base Build 13861376566:	0.002%
Covered Lines:	65142
Relevant Lines:	129182

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💛 - Coveralls

[dguittet]

LGTM