restructure: move bin/ and tests/ to src/

Also add symlinks from the old `bin/` and `tests/` locations to avoid
breaking scripts and other tools.

Motivations:

  * Scripts and tests no longer have to do dubious things like:

        require('ep_etherpad-lite/node_modules/foo')

    to access packages installed as dependencies in
    `src/package.json`.

  * Plugins can access the backend test helper library in a non-hacky
    way:

        require('ep_etherpad-lite/tests/backend/common')

  * We can delete the top-level `package.json` without breaking our
    ability to lint the files in `bin/` and `tests/`.

    Deleting the top-level `package.json` has downsides: It will cause
    `npm` to print warnings whenever plugins are installed, npm will
    no longer be able to enforce a plugin's peer dependency on
    ep_etherpad-lite, and npm will keep deleting the
    `node_modules/ep_etherpad-lite` symlink that points to `../src`.

    But there are significant upsides to deleting the top-level
    `package.json`: It will drastically speed up plugin installation
    because `npm` doesn't have to recursively walk the dependencies in
    `src/package.json`. Also, deleting the top-level `package.json`
    avoids npm's horrible dependency hoisting behavior (where it moves
    stuff from `src/node_modules/` to the top-level `node_modules/`
    directory). Dependency hoisting causes numerous mysterious
    problems such as silent failures in `npm outdated` and `npm
    update`. Dependency hoisting also breaks plugins that do:

        require('ep_etherpad-lite/node_modules/foo')

bin/deb-src/DEBIAN/control

@@ -1,9 +0,0 @@
-Package: etherpad
-Version: 1.3
-Section: base
-Priority: optional
-Architecture: i386
-Installed-Size: SIZE
-Depends:
-Maintainer: John McLear <john@mclear.co.uk>
-Description: Etherpad is a collaborative editor.  

bin/deb-src/DEBIAN/postinst

@@ -1,7 +0,0 @@
-#!/bin/bash
-# Start the services!
-
-service etherpad start
-echo "Give Etherpad about 3 minutes to install dependencies then visit http://localhost:9001 in your web browser"
-echo "To stop etherpad type 'service etherpad stop', To restart type 'service etherpad restart'".
-rm -f /tmp/etherpad.log /tmp/etherpad.err

bin/deb-src/DEBIAN/preinst

@@ -1,26 +0,0 @@
-#!/bin/bash
-
-# Installs node if it isn't already installed
-#
-# Don't steamroll over a previously installed node version
-# TODO provide a local version of node?
-
-VER="0.10.4"
-ARCH="x86"
-if [ `arch | grep 64` ]
-then
-  ARCH="x64"
-fi
-
-# TODO test version
-if [ ! -f /usr/local/bin/node ]
-then
-  pushd /tmp
-  wget -c "http://nodejs.org/dist/v${VER}/node-v${VER}-linux-${ARCH}.tar.gz"
-  rm -rf /tmp/node-v${VER}-linux-${ARCH}
-  tar xf node-v${VER}-linux-${ARCH}.tar.gz -C /tmp/
-  cp -a /tmp/node-v${VER}-linux-${ARCH}/* /usr/local/
-fi
-
-# Create Etherpad user
-adduser --system etherpad

bin/deb-src/DEBIAN/prerm

@@ -1,4 +0,0 @@
-#!/bin/bash
-
-# Stop the appserver:
-service etherpad stop || true

bin/deb-src/sysroot/etc/init/etherpad.conf

@@ -1,28 +0,0 @@
-description "etherpad"
-
-start on started networking
-stop on runlevel [!2345]
-
-env EPHOME=/opt/etherpad
-env EPLOGS=/var/log/etherpad
-env EPUSER=etherpad
-
-respawn
-
-pre-start script
-    cd $EPHOME
-    mkdir $EPLOGS                        ||true
-    chown $EPUSER $EPLOGS                ||true
-    chmod 0755 $EPLOGS                   ||true
-    chown -R $EPUSER $EPHOME/var         ||true
-    $EPHOME/bin/installDeps.sh >> $EPLOGS/error.log || { stop; exit 1; }
-end script
-
-script
-  cd $EPHOME/
-  exec su -s /bin/sh -c 'exec "$0" "$@"' $EPUSER -- node node_modules/ep_etherpad-lite/node/server.js \
-                        >> $EPLOGS/access.log \
-                        2>> $EPLOGS/error.log
-  echo "Etherpad is running on http://localhost:9001 - To change settings edit /opt/etherpad/settings.json"
-
-end script