Document curl installation thourgh macports

As this is a requirement for using Jack on Mac OS.

Change-Id: Iff92130f8d081e4fde10b589bcaead96a86df488
diff --git a/tools/README-jack-server.txt b/tools/README-jack-server.txt
index bc901e3..bdf7f93 100644
--- a/tools/README-jack-server.txt
+++ b/tools/README-jack-server.txt
@@ -7,6 +7,23 @@
 
 
 
+Setup for Mac OS
+----------------
+
+Jack server is automatically installed and started by android build but requires initial setup on
+Mac OS:
+
+  - Install MacPorts from http://www.macports.org/install.php
+    Make sure that /opt/local/bin appears in your path before /usr/bin. If not, please add the
+    following to your ~/.bash_profile file (If you do not have a .bash_profile file in your home
+    directory, create one):
+      export PATH=/opt/local/bin:$PATH
+
+  - Get curl package from MacPorts:
+      $ POSIXLY_CORRECT=1 sudo port install curl +ssl
+
+
+
 Starting the server
 -------------------