Fix case in titles

Author: mcol

src/functions-reference/array_operations.Rmd

@@ -3,11 +3,11 @@
 ```{r results='asis', echo=FALSE}
 if (knitr::is_html_output()) {
 cat(' * <a href="array-reductions.html">Reductions</a>\n')
-cat(' * <a href="array-size-and-dimension-function.html">Array Size and Dimension Function</a>\n')
-cat(' * <a href="array-broadcasting.html">Array Broadcasting</a>\n')
-cat(' * <a href="array-concatenation.html">Array Concatenation</a>\n')
+cat(' * <a href="array-size-and-dimension-function.html">Array size and dimension function</a>\n')
+cat(' * <a href="array-broadcasting.html">Array broadcasting</a>\n')
+cat(' * <a href="array-concatenation.html">Array concatenation</a>\n')
 cat(' * <a href="sorting-functions.html">Sorting functions</a>\n')
-cat(' * <a href="reversing-functions.html">Reversing Functions</a>\n')
+cat(' * <a href="reversing-functions.html">Reversing functions</a>\n')
 }
 ```
 
@@ -179,7 +179,7 @@ The squared Euclidean distance between x and y
 `real` **`squared_distance`**`(row_vector x, row_vector[] y)`<br>\newline
 The Euclidean distance between x and y
 
-## Array Size and Dimension Function
+## Array size and dimension function
 
 The size of an array or matrix can be obtained using the `dims()`
 function.  The `dims()` function is defined to take an argument
@@ -237,7 +237,7 @@ can be any type, but the size is just the size of the top level array,
 not the total number of elements contained. For example, if `x` is of
 type `real[4,3]` then `size(x)` is 4.
 
-## Array Broadcasting {#array-broadcasting}
+## Array broadcasting {#array-broadcasting}
 
 The following operations create arrays by repeating elements to fill
 an array of a specified size.  These operations work for all input
@@ -313,7 +313,7 @@ After the assignment to `b`, the value for `b[j,k,m,n]` is equal to
 `a[m,n]` where it is defined, for `j` in `1:3`, `k` in `1:4`, `m` in
 `1:5`, and `n` in `1:6`.
 
-## Array Concatenation {#array-concatenation}
+## Array concatenation {#array-concatenation}
 
 <!-- T; append_array; (T x, T y); -->
 \index{{\tt \bfseries append\_array }!{\tt (T x, T y): T}|hyperpage}
@@ -335,7 +335,7 @@ Any mismatches will cause an error to be thrown.
  x3 = append_array(x1, x2);
 ```
 
-## Sorting Functions {#sorting-functions}
+## Sorting functions {#sorting-functions}
 
 Sorting can be used to sort values or the indices of those values in
 either ascending or descending order.  For example, if `v` is declared
@@ -410,7 +410,7 @@ Number of components of v less than v[s]
 `int` **`rank`**`(int[] v, int s)`<br>\newline
 Number of components of v less than v[s]
 
-## Reversing Functions {#reversing-functions}
+## Reversing functions {#reversing-functions}
 
 Stan provides functions to create a new array by reversing the order of
 elements in an existing array. For example, if `v` is declared as a real