replaces instance variable in view by methods in controller

Replaces every instance variable in the view layer by a method call to the controller. This is done in order to:

1) better separate concerns.
2) Lazy loading of objects that might be used by a block. As the purpose of the plugin is to allow the user to choose from a list of available blocks, not all blocks will be used all the times. This also means that not all information is required to be loaded all the time. With this commit, we load only what is required for the current block selection by having each block call a method that loads the information it requires.
limits the number of members initially shown, adds ajax reloading for more
releases 2.1.0

performance optimization