Session creation decomposed out of uploader.php
tabs -> spaces
Filename normalize rules & behavior changed

eg. "nová složka" from user's input will be saved as "nova-slozka" (URL-friendly)
tabs -> spaces
Merge branch 'feature/sessions'

Conflicts:
	core/autoload.php
	core/class/session.php
	core/class/uploader.php
Merge branch 'feature/filename-normalize'

Conflicts:
	conf/config.php