Use abbreviations with dots.

core/deco.c

@@ -43,7 +43,7 @@ struct buehlmann_config {
 	double gf_high;			//! gradient factor high (at surface).
 	double gf_low;			//! gradient factor low (at bottom/start of deco calculation).
 	double gf_low_position_min;	//! gf_low_position below surface_min_shallow.
-	bool gf_low_at_maxdepth;	//! if true, gf_low applies at max depth instead of at deepest ceiling.
+	bool gf_low_at_maxdepth;	//! if true, gf_low applies at max. depth instead of at deepest ceiling.
 };
 
 struct buehlmann_config buehlmann_config = {

core/dive.c

@@ -663,7 +663,7 @@ void finish_sample(struct divecomputer *dc)
  * new ones.
  *
  * Why? Because a dive computer may well actually track the
- * max depth and mean depth at finer granularity than the
+ * max. depth and mean depth at finer granularity than the
  * samples it stores. So it's possible that the max and mean
  * have been reported more correctly originally.
  *
@@ -2440,7 +2440,7 @@ static int find_sample_offset(struct divecomputer *a, struct divecomputer *b)
  * difference?
  *
  * So for example, we'd expect different dive computers to give different
- * max depth readings. You might have them on different arms, and they
+ * max. depth readings. You might have them on different arms, and they
  * have different pressure sensors and possibly different ideas about
  * water salinity etc.
  *

core/units.h

@@ -53,7 +53,7 @@ extern "C" {
  * Also strive to use units that can not possibly be mistaken for a
  * valid value in a "normal" system without conversion. If the max
  * depth of a dive is '20000', you probably didn't convert from mm on
- * output, or if the max depth gets reported as "0.2ft" it was either
+ * output, or if the max. depth gets reported as "0.2ft" it was either
  * a really boring dive, or there was some missing input conversion,
  * and a 60-ft dive got recorded as 60mm.
  *