No a single detection is hardly confirmation and usually considered an FP, more so if there is a detection from a lesser known AV.
In your case you are going to have to send the sample to avast for further analysis. If this has been on your system for some time and is only now detected it is possibly that it is an FP as the Win32:Trojan-gen is a generic signature and also gdata uses avast as one of its two scanners, so yours is effectively only one detection.
Send the sample to avast as a False Positive:
Open the chest and right click on the file and select 'Submit to virus lab...' complete the form and submit, the file will be uploaded during the next update.
- In the meantime (if you accept the risk), add the full path to the file to the exclusions lists:
File System Shield, Expert Settings, Exclusions, Add and
avast Settings, Exclusions
Restore it to its original location, periodically check it (scan it in the chest), there should still be a copy in the chest even though you restored it to the original location. When it is no longer detected then you can also remove it from the File System Shield and avast Settings, exclusions lists.
If you don't accept that risk, you could use another text editor for the time being (I use editpad lite as my text editor of choice) whilst it is being analysed.
