Some additional repos to consider:
thinkshout/salesforce — Rewrite of the Drupal Salesforce Suite using the REST API.
cakephp-salesforce — A Salesforce Enterprise Datasource for CakePHP allowing manipulation of Salesforce objects through Cakes ORM
genesis-global/salesforce-bundle — Symfony bundle for Salesforce REST client
Salesforce-Web2lead — Salesforce Web2lead framework - sending leads directly into Salesforce CRM with validation
mage2pro/salesforce — Salesforce integration with Magento 2
Once a week...... I send out a list of most interesting PHP libraries and apps.
Want to get it?