Revert "fix build on macosx"

This reverts commit 94fe661233f69faa8cfbcb71d0202eb9bca4600f.
move sources to src
support static build

This change backport the static build from rcouch.

A static build of spidermonkey is the default. To build with the
libraries installed you can pass the parameter `libs=shared` to the
make.

By default couch_collate is using ICU installed on the system except if
you pass the option `icu=static` to the Make.

At anytime you can override the compilation environnement with the
following variables:

JS_CFLAGS
JS_LIBS
ICU_CFLAGS
ICU_LDFLAGS
remove useless files
only put the files we need in share/
move src/apps/fauxton -> src/share/fauxton
move src/apps/couchjs-node -> src/addons/couchjs-node
move test -> src/test
move src/apps/couch_rel -> src/support/couch_rel

couch_rel is not a couchdb application, it has for only purpose to
provide etop to the release.