Update .gitignore

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

.gitignore

@@ -1,3 +1,18 @@
 *~
 *.o
 open-channel
+open-anchor-scriptsigs
+leak-anchor-sigs
+open-commit-sig
+check-commit-sig
+check-anchor-scriptsigs
+get-anchor-depth
+create-steal-tx
+create-commit-spend-tx
+close-channel
+create-close-tx
+update-channel
+update-channel-accept
+update-channel-signature
+update-channel-complete
+create-commit-tx