Feature: Quick-fill seed flags

[FelicitusNeko]

I'd like to suggest something for rolling new seeds with specific flags:

• Input the flag string (say 1CBF89 for the current tournament's flags)
• Hit "New"
• A new seed is generated with the flags represented by the flag string (1234[...]1CBF89)

If the flag string is too short (I'm not sure if it's six or eight chars), front-fill with zeroes (so it would become 001CBF89 if it needs to be eight chars).

[Jarno458]

This works if you prefix it with 000000's yourself