added dependency check

tests/unittests.cfg

@@ -27,6 +27,22 @@ md5msg   = 66b8c4ca9e5d2a7e3c0559c3cdea3d50
 
 include keys.cfg
 
+<test check-dependencies>
+  <test check-dependencies-perl>
+    cmd = perl -MYAML-e 'print 1'
+    expect = 1
+  </test>
+  <test check-dependencies-shell>
+    cmd = which mdmfs
+    expect = /mdmfs/
+  </test>
+  <test check-dependencies-pcp>
+    cmd = ls $pcp
+    expect = /pcp/
+  </test>
+</test>
+
+
 <test check-show-help>
   cmd    = $pcp -h
   expect = /export/