add travis support

[m6w6/ext-psi] / travis / pecl

diff --git a/travis/pecl b/travis/pecl
new file mode 160000 (submodule)
index 0000000..5fa813b
--- /dev/null
+++ b/travis/pecl
@@ -0,0 +1 @@
+Subproject commit 5fa813b43612f3467f029f6681ebe5591ac6d275