Allow defining multiple announce urls for one tracker

[buthed010203]

Description

Previously, if a tracker had two announce URLs hello.world and foo.bar, the tracker block would look something like

tracker:
  hello.world:
    tag: sometag
  foo.bar:
    tag: sometag

Obviously this isn't ideal, this PR allows for pipes in tracker definitions so that the example above would become

tracker:
  hello.world|foo.bar:
    tag: sometag

While this isn't as much of an issue now that share ratios are handled in a different block, this condensed format should make it easier to keep track of a large number of trackers (no pun intended).

I am unsure as to where this should be documented so I have not done so for now

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the docstring for new or existing methods
• I have modified this PR to merge to the develop branch