Single p2 feature for all archs

[piotrtomiak]

I would like to suggest a single feature for the update site, which could automatically provide appropriate bundle. It would be as follows.

<feature
      id="com.eclipsesource.j2v8.feature"
      label="%featureName"
      version="3.1.6.qualifier"
      provider-name="%featureProvider">

   <description>
      %description
   </description>

   <copyright>
      %copyright
   </copyright>

   <license url="%licenseURL">
      %license
   </license>

   <plugin
         id="com.eclipsesource.j2v8.linux_x86_64"
         os="linux"
         arch="x86_64"
         download-size="0"
         install-size="0"
         version="3.1.6"
         unpack="false"/>

   <plugin
         id="com.eclipsesource.j2v8.linux_x86"
         os="linux"
         arch="x86"
         download-size="0"
         install-size="0"
         version="3.1.6"
         unpack="false"/>

   <plugin
         id="com.eclipsesource.j2v8.macosx_x86_64"
         os="macosx"
         arch="x86_64"
         download-size="0"
         install-size="0"
         version="3.1.6"
         unpack="false"/>

   <plugin
         id="com.eclipsesource.j2v8.win32_x86_64"
         os="win32"
         arch="x86_64"
         download-size="0"
         install-size="0"
         version="3.1.6"
         unpack="false"/>

   <plugin
         id="com.eclipsesource.j2v8.win32_x86"
         os="win32"
         arch="x86"
         download-size="0"
         install-size="0"
         version="3.1.6"
         unpack="false"/>

</feature>

@irbull if you wish I can create a PR for this.

[irbull]

We are going to scope this repo to holding only the core and builds for Android. Others are free to provide downstream repos for other platforms, but unfortunately, I don't have the cycles for that. Please see #441 for more information. Since a p2 feature isn't needed for Android, I'm closing this as out of scope.