Add new Classes for handling PHP file uploads

- Api\Request\Files
- Api\Request\Files\Upload
Replace old files system with new classes in Request Class
Update references to headers and parameters in Request Class to match new formats
Rename properties in Api\Request\Files\Upload Class

- Changed from matching PHP array keys
Update parse() method to handle array based field name structure

- Also uses new Upload field names
Add quick check method for file exists to the Api\Request\Files\Upload Class
Add hashing method to the Api\Request\Files\Upload Class
Merge branch 'feature/uploadFunctionality' into feature/requestFiles
Add Filter Class the the Api\Request\Files namespace
Implement upload filtering for selecting specific files in Api\Request\Files Class
Merge branch 'feature/uploadFiltering' into feature/requestFiles
Merge branch 'feature/requestFiles' into develop