Improvements

• Updated Credits store's backend libraries due to security policy changes.
• Alliance invitation menu now makes sure the airline is not listed as a possible invitee if it shares HQ/base with any other existing alliance member. (n.b. this does not apply to alliance application from the applying airlines' side since this still within the old UI)

Fixes

• Low Credits balance e-mails were being sent out too often.
• Notifications of in-game messages did not always pop to the main navigation's notification balloon.
• Scheduling page's search data became sometimes corrupted preventing the page load.
• Alliance icon of an alliance still in founding state ( = not yet offically formed) showed up in route planning's airline schedule listing.
• If an aircraft was in long-term storage and a model conversion (e.g. to freighter) was performed, and the plane was taken out of the long-term storage while the conversion maintenance was still ongoing, the D check included in the conversion was not being performed. Fixed by disabling the long-term storage removal while conversion maintenance is ongoing.