v0.30: Renew copied OTP

You can now specify whether a copied OTP shall be renewed.
Options:
- No renewal of copied OTP
- Renew once if it will expire soon (default)
- Renew until KeePass clears the clipboard

No renewal of copied OTP:
This is the previous behaviour. You copy an OTP and the current value will remain in the clipboard until it is cleared.

Renew once if it will expire soon:
If the copied OTP will expire within 5 seconds, a new OTP will be copied to the clipboard as well *once*.
This allows to e. g. select the correct field in your browser manually (focus got lost, ...)

Renew until KeePass clears the clipboard:
While the clipboard countdown is ticking, a new OTP will be copied to the clipboard whenever the copied one expires.
This has an effect only if you set your clipboard timeout to a higher value than the OTP timeout (usually 30 seconds)

If a copied OTP is renewed, the clipboard countdown will *NOT* be restarted.

In addition, all KeePassOTP specific data (time correction URL, flag in case a 2nd db is used for OTP secrects) is moved to entries's custom data section