0.7.0.rc1

ChangeLog

* IDLE / READY states correction
* Improve error callbacks
* File and Folder name validation
* Registration headers update
* Create directory function does nothing if folder already exists
* get_free_space() replaced by get_space_info(), added total size info
* Make on the fly download throttling possible
* Add mesh bed levelling event
* Added command_id to telemetry, if there's a command in progress
* 4xx responses handling change
* Add sheet settings and mbl data
* Add Transfer ID as a 64-bit int
* Added new SET_PRINTER_READY / CANCEL_PRINTER_READY cmds
* Inotify fix - handling nested files
* Introduce a new conditions system
* Added StorageType enum to const
* TRANSFER_INFO improvement
* Make downloads from connect time out after 30s of inactivity
* Send state in every Event