valgrind: add page (#1407)

* valgrind: add page

* valgrind: tweak Memcheck example

Provide alternate, clearer syntax that functions the same and update
description accordingly.

* valgrind: correct program description

* valgrind: add list of common tools

* valgrind: remove general form example and add no-option example

* valgrind: replace period with colon in example 1

pages/common/valgrind.md

@@ -0,0 +1,20 @@
+# valgrind
+
+> Wrapper for a set of expert tools for profiling, optimizing and debugging programs.
+> Commonly used tools include `memcheck`, `cachegrind`, `callgrind`, `massif`, `helgrind`, and `drd`.
+
+- Use the (default) Memcheck tool to show a diagnostic of memory usage by `program`:
+
+`valgrind {{program}}`
+
+- Use Memcheck to report all possible memory leaks of `program` in full detail:
+
+`valgrind --leak-check=full --show-leak-kinds=all {{program}}`
+
+- Use the Cachegrind tool to profile and log CPU cache operations of `program`:
+
+`valgrind --tool=cachegrind {{program}}`
+
+- Use the Massif tool to profile and log heap memory and stack usage of `program`:
+
+`valgrind --tool=massif --stacks=yes {{program}}`