Introduce database updates time dependent #107
Description
Is your feature request related to a problem? Please describe.
Using own programs with a database update at the beginning might be a problem if they are run very often.
Describe the solution you'd like
TDB should write a local file into its local database with the date/timestamp of the last performed database update. It should be configurable what is the time difference in days when the updater should download the new transistor files.