moved progress stuff to new plugin

Change-Id: I132568ca3eacbc518ce13460cf762a1388f1d56a
    added another stage for plugins

    there are now 3 stages of cxx-plugins. each plugin needs a plugin_name/plugin.rb with a cxx_plugin block.
    depending on the stage the block has to take a different number of arguments.

    1. at first plugins with no argument are loaded (before the project-files are evaluated)
    2. directly after this all toolchains are initialized (the toolchains should have no arguments to the block)
    3. after all building blocks the rest of the plugin with 3 arguments to the block are loaded

    TODO .. join the first two stages .. both are plugins with no arguments and this is something which distinguishes them from the plugins with 3 arguments

TODO ... move progress_count to cxxproject_progress

Change-Id: I69332ca0afc7af80482fd180521f44fa5a404c6f
moved progress monkey patches to cxxproject_progress

Change-Id: I7849744fb6dcbf575ddccc6caeff9d6239ac19fd
simplified plugin stages

1. plugins with a no arg cxx_plugin are loaded after the main cxxproject classes are loaded (e.g. toolchains and plugins that need to monkey-patch rake further)
2. plugins with a thre arg cxx_plugin are loaded after all project.rb files are evaluated. they get access to cxx, the buildingblocks and a logger

Change-Id: Ic6026937f51f5274fb51063b7615911bed478626
moved rake_listener_spec to cxxproject_progress

Change-Id: I6ec78144d4e246f9def1433072246274af35963d