Fixed x/y mixup in 'axes'

Removed 'plot-tick-skip' parameter

Merge into 5.2
(cherry picked from commit 7270c27141)

collects/plot/common/parameters.rkt

@@ -38,7 +38,6 @@
 (defparam plot-legend-box-alpha alpha (real-in 0 1) 2/3)
 
 (defparam plot-tick-size (>=/c 0) 10)
-(defparam plot-tick-skip exact-positive-integer? 2)
 
 (defparam plot-title (or/c string? #f) #f)
 (defparam plot-x-label (or/c string? #f) "x axis")

collects/plot/common/ticks.rkt

@@ -42,7 +42,7 @@
     (map tick ps labels majors)))
 
 (defproc (default-ticks-fun [x-min real?] [x-max real?]) (listof tick?)
-  (linear-ticks (plot-tick-skip) x-min x-max))
+  (linear-ticks 2 x-min x-max))
 
 (defproc (auto-contour-zs [z-min real?] [z-max real?]) (listof real?)
   (let* ([zs  (map tick-p (default-ticks-fun z-min z-max))]

collects/plot/plot2d/decoration.rkt

@@ -76,8 +76,8 @@
                [#:x-ticks? x-ticks? boolean? (x-axis-ticks?)]
                [#:y-ticks? y-ticks? boolean? (y-axis-ticks?)]
                ) (listof renderer2d?)
-  (list (x-axis x #:ticks? x-ticks?)
+  (list (x-axis y #:ticks? x-ticks?)
-        (y-axis y #:ticks? y-ticks?)))
+        (y-axis x #:ticks? y-ticks?)))
 
 ;; ===================================================================================================
 ;; Polar axes

collects/plot/plot2d/plot.rkt

@@ -128,7 +128,6 @@
   (define line-width (plot-line-width))
   (define legend-box-alpha (plot-legend-box-alpha))
   (define tick-size (plot-tick-size))
-  (define tick-skip (plot-tick-skip))
   (define x-transform (plot-x-transform))
   (define y-transform (plot-y-transform))
   (define z-transform (plot-z-transform))
@@ -144,7 +143,6 @@
                        [plot-line-width        line-width]
                        [plot-legend-box-alpha  legend-box-alpha]
                        [plot-tick-size         tick-size]
-                       [plot-tick-skip         tick-skip]
                        [plot-x-transform       x-transform]
                        [plot-y-transform       y-transform]
                        [plot-z-transform       z-transform]

collects/plot/plot3d/plot.rkt

@@ -150,7 +150,6 @@
   (define line-width (plot-line-width))
   (define legend-box-alpha (plot-legend-box-alpha))
   (define tick-size (plot-tick-size))
-  (define tick-skip (plot-tick-skip))
   (define x-transform (plot-x-transform))
   (define y-transform (plot-y-transform))
   (define z-transform (plot-z-transform))
@@ -170,7 +169,6 @@
                        [plot-line-width         line-width]
                        [plot-legend-box-alpha   legend-box-alpha]
                        [plot-tick-size          tick-size]
-                       [plot-tick-skip          tick-skip]
                        [plot-x-transform        x-transform]
                        [plot-y-transform        y-transform]
                        [plot-z-transform        z-transform]

collects/plot/scribblings/params.scrbl

@@ -84,7 +84,6 @@ See @(racket ->pen-color) and @(racket ->brush-color) for details on how PLoT in
 @doc-apply[plot-legend-box-alpha]{The opacity of the filled rectangle behind the legend entries.}
 
 @doc-apply[plot-tick-size]{The length of tick lines, in drawing units.}
-@doc-apply[plot-tick-skip]{Controls the spacing between major ticks for renderers that use the default tick function, such as the renderers returned by @(racket function) and @(racket surface3d). With the default value @(racket 2), every other tick is major. A tick at @(racket 0) is always major. Major ticks are thicker and labeled; minor ticks are thinner and unlabeled.}
 
 @doc-apply[plot-title]
 @doc-apply[plot-x-label]

collects/plot/tests/plot2d-tests.rkt

@@ -11,6 +11,8 @@
 
 (plot empty #:x-min -1 #:x-max 1 #:y-min -1 #:y-max 1)
 
+(plot (list (axes 1 2) (function values -4 4)))
+
 (time (plot (function values 0 1000)))
 
 (parameterize ([plot-background  "black"]