Improve wording of Theorem 3.3

[amdw]

Theorem 3.3 (the first canonical play result) should be reworded in a more mathematical way.

The theorem itself should state the value of P in terms of P_t, P_d, n and the minimum number of coins which must be sacrificed to make a double-dealing move.

The proof should then prove this by explicitly using the preceding lemma to show that all options besides these two can have no effect on the value of the position.

The informally worded implications of the theorem should remain.

[amdw]

The other theorems in the section would also benefit from similar rewording. Definitions could be introduced in the theorems which are then used in the proofs.

[amdw]

Actually, theorem 3.1 implicitly depends on 3.3, as its proof assumes that there are only two possibilities which need to be considered, which is precisely what 3.3 proves. As such, perhaps this whole section needs a more fundamental restructuring.