Remove obsolete code from easyshare Studio project

Easyshare addon breaks the search in Nuxeo, especially all features related to Elasticsearch:

• screenshot1: the aggregates are all filled
• screenshot2: the aggregates are empty

Looking at the code generated by Studio (extensions.xml), I found a lot of obsolete code. Moreover Studio configuration does not show these pieces of configuration.

For example, a content view called default_search is defined whereas nothing appears in the Search tab of Studio.