Target "tests" now only builds the modules tagged as "tests"

But not install them.
This prevents "make tests" polluting system.img or userdata.img.
We have new mechanism to build and package up modules into zip file in
build/core/tasks/tools.
Change package-modules.mk to install DATA/ instead of data/ in the
zip file; Better handle of module name conflicting.

Bug: 13585955
Change-Id: I7586a8c7995b984c9ead0ba2fa84dd5d2dd20bd1
diff --git a/core/main.mk b/core/main.mk
index 4e00e70..c212858 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -998,7 +998,7 @@
 # umbrella targets to assit engineers in verifying builds
 .PHONY: java native target host java-host java-target native-host native-target \
         java-host-tests java-target-tests native-host-tests native-target-tests \
-        java-tests native-tests host-tests target-tests
+        java-tests native-tests host-tests target-tests tests
 # some synonyms
 .PHONY: host-java target-java host-native target-native \
         target-java-tests target-native-tests
@@ -1008,6 +1008,7 @@
 target-native : native-target
 target-java-tests : java-target-tests
 target-native-tests : native-target-tests
+tests : host-tests target-tests
 
 
 .PHONY: lintall