let user configure limits to network traffic

[mfrasca]

each time I start telega, it just downloads the new stuff, which is good.
however, I'm often at locations where I would not want to automatically download larger media files when I open telega. rather, I'd like to be able to instruct telega what to do at startup.

• I guess most users would want to just download every attachment.
• if you only have an expensive connection, you may want to ignore larger attachments, according to a threshold.
• when you have an expensive connection, but can go to a nearby library, you may want to be asked what to do.

maybe you want to add two configuration items, something like:

• threshold: ignore / respect / ask
• threshold value in Mbytes

[brettgilio]

Currently you must initiate downloading with telega. Is this issue still valid?

[zevlg]

Currently you must initiate downloading with telega. Is this issue still valid?

Yeah, keep this please