Implemented Arrows (#864)

[RoiEXLab]

This adresses #864 and fixes some scaling issues (The Route was slightly offset when scaling to extreme values 15% etc.)
Screenshots:

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This change is

[RoiEXLab]

Hmm weird... it seems, that we have another flaky test out here:

games.strategy.engine.chat.ChatFloodControlTest > testDeny FAILED

    java.lang.AssertionError

        at org.junit.Assert.fail(Assert.java:86)

        at org.junit.Assert.assertTrue(Assert.java:41)

        at org.junit.Assert.assertFalse(Assert.java:64)

        at org.junit.Assert.assertFalse(Assert.java:74)

        at games.strategy.engine.chat.ChatFloodControlTest.testDeny(ChatFloodControlTest.java:21)

[DanVanAtta]

you're not hitting any local state, looks like you can mark these private methods as static (note, static on private methods is a good thing since it makes the method easier to understand, provided you do not modify any static state. Static on public methods is bad, creates static coupling that hurts cohesion and makes testing difficult)

[DanVanAtta]

Some good stuff, but a few things can be improved

[RoiEXLab]

@DanVanAtta done

[DanVanAtta]

Extract the one to a constant, then you can calculate the -3 value.
Idea is to capture any relationships between lines of code that are known to exist, so everything that needs to change, changes when you change the one thing.

[RoiEXLab]

@DanVanAtta done