Added symlinks to libbe and becommands in interfaces/email/interactive.

With this set-up, be-handle-mail run from its own directory will load
your working-state BE setup, not your system-wide BE installation.

diff --git a/interfaces/email/interactive/becommands b/interfaces/email/interactive/becommands
new file mode 120000 (symlink)
index 0000000..8af773c
--- /dev/null
+++ b/interfaces/email/interactive/becommands
@@ -0,0 +1 @@
+../../../becommands
\ No newline at end of file

diff --git a/interfaces/email/interactive/libbe b/interfaces/email/interactive/libbe
new file mode 120000 (symlink)
index 0000000..7d18612
--- /dev/null
+++ b/interfaces/email/interactive/libbe
@@ -0,0 +1 @@
+../../../libbe
\ No newline at end of file