[3.x] Rename "extract()" to "extract_from()" for entities

[MasterGroosha]

Is your feature request related to a problem? Please describe.
The current way to extract entity from message text looks like

for item in message.entities:
    item.extract(message.text)

This sounds weird, since we extract entity from message, not vice versa.

Describe the solution you'd like
Rename extract to extract_from. For example:

for item in message.entities:
    item.extract_from(message.text)