Change membership benefits table and boxes to extbase plugins

Once we connect the voucher management with hubspot, we need to deliver data in a structured way.

the tables are prepared already: name varchar(255) DEFAULT '' NOT NULL, subheader varchar(255) DEFAULT '' NOT NULL, description text, NOT Null, logo text NOT NULL, personal_membership tinyint(4) DEFAULT '0' NOT NULL, academic_membership tinyint(4) DEFAULT '0' NOT NULL, no_filter tinyint(4) DEFAULT '0' NOT NULL, event_vouchers_number int(11) unsigned DEFAULT '0' NOT NULL, event_voucher_value double(11,2) DEFAULT '0.00' NOT NULL, event_vouchers_number_academic int(11) unsigned DEFAULT '0' NOT NULL,

Todos:

• Add TCA for memberships
• Add plugin to render membership benefits table (normal, academic)
• Add plugin to render membership teasers (editor should select, which memberhip should be displayed)
• Add JSON export for membership benefits