doc: Add 'guix environment' examples.

* doc/environment-gdb.scm: New file.
* doc.am (EXTRA_DIST): Add it.
* doc/guix.texi (Invoking guix environment): Clarify wording of the first
  example.  Add a --ad-hoc example upfront.  Add an example for '-e', and one
  for '-l'.

1 files changed, 2 insertions, 1 deletions

diff --git a/doc.am b/doc.am
index 9d72b11caa..8a65b8d90d 100644
--- a/doc.am
+++ b/doc.am
@@ -24,7 +24,8 @@ EXTRA_DIST +=					\
   doc/fdl-1.3.texi				\
   doc/images/bootstrap-graph.dot		\
   doc/images/bootstrap-graph.eps		\
-  doc/images/bootstrap-graph.pdf
+  doc/images/bootstrap-graph.pdf		\
+  doc/environment-gdb.scm
 
 OS_CONFIG_EXAMPLES_TEXI =			\
   doc/os-config-bare-bones.texi			\