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version 0.2.0, 2016-10-07
- closed():					new function: Closed respirometry
- import_presens():	new function: Import data from a PreSens O2 transmitter
- import_witrox():	new function: Import data from a Loligo Systems Witrox transmitter
- scale_MO2():			new function: Scale metabolic rate by size
- conv_o2():				added support for mmol_per_l and mmol_per_kg
- flush_o2():				added support for calculating any parameter from the others, not just calculating final O2.
- mean_pH():				returns an NA rather than error when pH = NULL
- co2_*.R():				improved documentation
- flush_water():		improved documentation
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version 0.1.2, 2016-09-02
- guess_TA():			now allows calculations if salinity is <= 5 psu outside the bounds, but with a warning.
- guess_TA():			fixed a bug where an error occurred if any NAs were provided
- predict_pH():			fixed a bug where an error occurred if any NAs were provided
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version 0.1.1, 2016-08-23
- predict_pH():			fixed a bug where a single NA was returned if any NAs were provided
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version 0.1.0, 2016-08-22
- co2_add():			new function
- co2_flush():			new function
- co2_rate():			new function
- conv_NH4():			new function
- conv_o2():			new function
- correct_bubble():		new function
- flush_carb():			new function
- flush_o2():			new function
- flush_water():		new function
- goal_flush_pH():		new function
- guess_TA():			new function
- guess_when():			new function
- max_MO2():			new function
- mean_pH():			new function
- min_flow():			new function
- peri_pump():			new function
- predict_NH4():		new function
- predict_pH():			new function
- Q10():				new function
- RQ():					new function
