Adding Event trigger average for all dimensions

[gviejo]

Additionally : changing jitted_functions.py to _jitted_functions.py

[coveralls]

Pull Request Test Coverage Report for Build 7701976961

• 16 of 41 (39.02%) changed or added relevant lines in 8 files are covered.
• 3 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-59.5%) to 23.682%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pynapple/core/ts_group.py	2	4	50.0%
pynapple/process/perievent.py	0	3	0.0%
pynapple/process/tuning_curves.py	1	21	4.76%

Files with Coverage Reduction	New Missed Lines	%
pynapple/core/time_series.py	1	23.25%
pynapple/process/tuning_curves.py	2	4.24%

Totals
Change from base Build 7673631933:	-59.5%
Covered Lines:	674
Relevant Lines:	2393

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 7701976961

• 16 of 41 (39.02%) changed or added relevant lines in 8 files are covered.
• 3 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.1%) to 83.089%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pynapple/core/ts_group.py	2	4	50.0%
pynapple/process/perievent.py	0	3	0.0%
pynapple/process/tuning_curves.py	1	21	4.76%

Files with Coverage Reduction	New Missed Lines	%
pynapple/core/time_series.py	1	49.86%
pynapple/process/tuning_curves.py	2	31.1%

Totals
Change from base Build 7673631933:	-0.1%
Covered Lines:	2040
Relevant Lines:	2393

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💛 - Coveralls