Core gameplay systems:
- added a guided tutorial for the first 6 introductory quests
- added a clear indication of XP required and ETA for skill training level up
- added information in the quests panel about next quest unlock if the user does not meet any requirement
- In squad selection view: added mission recap, operative faction details.
- Updated the operation and roster counters to clearly differentiate between active/available operations and waiting/total units
- built a custom drop-down that should be compatible with Linux builds
- minor GUI fixes

Recruitment:
- added owned status

Roster:
- added a grid display for owned units
- added a "Star Up all available units" button to star up multiple units at once

LINUX:
- added a tentative Linux version that should also fix audio issues