geom/stat docs tweaks (#2625)

Fixes #2618

Author: hadley

R/geom-.r

@@ -9,8 +9,7 @@ NULL
 #'
 #' Each of the `Geom*` objects is a [ggproto()] object, descended
 #' from the top-level `Geom`, and each implements various methods and
-#' fields. To create a new type of Geom object, you typically will want to
-#' implement one or more of the following:
+#' fields.
 #'
 #' Compared to `Stat` and `Position`, `Geom` is a little
 #' different because the execution of the setup and compute functions is
@@ -19,7 +18,10 @@ NULL
 #' means there is no `setup_params` because it's hard to communicate
 #' the changes.
 #'
-#'   - Override either `draw_panel(self, data, panel_params, coord)` or
+#' To create a new type of Geom object, you typically will want to
+#' override one or more of the following:
+#'
+#'   - Either `draw_panel(self, data, panel_params, coord)` or
 #'     `draw_group(self, data, panel_params, coord)`. `draw_panel` is
 #'     called once per panel, `draw_group` is called once per group.
 #'
@@ -35,7 +37,7 @@ NULL
 #'     a coord method.
 #'
 #'     You must always call `coord$transform(data, panel_params)` to
-#'     get the (position) scaled data for plotting. convert. To work with
+#'     get the (position) scaled data for plotting. To work with
 #'     non-linear coordinate systems, you typically need to convert into a
 #'     primitive geom (e.g. point, path or polygon), and then pass on to the
 #'     corresponding draw method for munching.
@@ -47,7 +49,7 @@ NULL
 #'     render the geom.
 #'   - `default_aes`: A list (generated by [aes()] of
 #'     default values for aesthetics.
-#'   - `reparameterise`: Converts width and height to xmin and xmax,
+#'   - `setup_data`: Converts width and height to xmin and xmax,
 #'     and ymin and ymax values. It can potentially set other values as well.
 #' @rdname ggplot2-ggproto
 #' @format NULL

R/stat-.r

@@ -7,9 +7,9 @@
 #' Each of the `Stat*` objects is a [ggproto()] object, descended
 #' from the top-level `Stat`, and each implements various methods and
 #' fields. To create a new type of Stat object, you typically will want to
-#' implement one or more of the following:
+#' override one or more of the following:
 #'
-#'   - Override one of :
+#'   - One of :
 #'     `compute_layer(self, data, scales, ...)`,
 #'     `compute_panel(self, data, scales, ...)`, or
 #'     `compute_group(self, data, scales, ...)`.