Merge pull request #688 from JuliaSymbolics/ChrisRackauckas-patch-1

Fix the first tutorial...

docs/src/tutorials/symbolic_functions.md

@@ -274,7 +274,7 @@ new functions. For example, let's register a new function `h`:
 
 ```julia
 h(x, y) = x^2 + y
-@register h(x, y)
+@register_symbolic h(x, y)
 ```
 
 Now when we use `h(x, y)`, it is a symbolic expression and doesn't expand:
@@ -500,4 +500,4 @@ rows, cols, _ = findnz(sj)
 out = sparse(rows, cols, zeros(length(cols)), size(sj)...) # pre-allocate, and correct structure
 myf = eval(last(f_expr))
 myf(out, rand(N)) # note that out matches the sparsity structure of sj
-```
+```