Allow dialogs to be opened with parameter

[zorfmorf]

Example:

Seed vendor karen needs to start her dialog in three different ways:

• Player tries to walk up the stairs
• Player talks to her behind the counter
• Player talks to her as a customer

We don't want to have three different dialogs for this scenario. A good approach would be, that each line can have a condition. Dialog class just skips lines for which conditions are not fulfilled

[zorfmorf]

Done and fixed for seed shop dialogues