Updates to Install Script Docs

This patch fixes the install script's documentation.

.build/install

@@ -7,34 +7,34 @@
 #
 # to install the latest version of REX-Ray simply execute:
 #
-#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -
+#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh
 #
 # however, this script will also allow users to install specific
 # versions of REX-Ray and even supports the discovery of those versions.
 # for example, to list the available REX-Ray packages use the "list"
 # command like so:
 #
-#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s list -
+#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- list
 #
 # this will emit the following curl commands to demonstrate how to
 # install one or more of the available packages, "unstable", "staged",
 # and "stable".
 #
-#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s unstable -
-#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s staged -
-#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s stable -
+#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- unstable
+#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- staged
+#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- stable
 #
 # again, the "list" command outputs the curl commands to perform
 # installations, not how to traverse deeper into the package structure.
 # however, it's not hard to do that traversal. for example, to list the
 # contents of the "stable" package we'd execute:
 #
-#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s list stable -
+#  curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- list stable
 #
 # the above command would emit somthing similar to:
 #
-#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s stable 0.2.0 -
-#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s stable latest -
+#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- stable 0.2.0
+#    curl -sSL https://dl.bintray.com/emccode/rexray/install | sh -s -- stable latest
 #
 # as you can see, to traverse the structure, we simply insert the
 # command "list" as the first argument after the "-s" flag.