added three libs:

+  <project path="external/readline" name="RichardLuo/droid.external.readline" remote="github" />
+  <project path="external/coho" name="RichardLuo/droid.external.coho" remote="github" />
+  <project path="external/termcap" name="RichardLuo/droid.external.termcap" remote="github" />

Change-Id: I90b43a4ab522014c7d8579e4443a6a73d31f6fb4