refactor: add x & y labels on plots (#54)

Also change one plot to percents like in the book

Author: kir0ul

notebooks/Chapter06_Cliff_Walking.jl

@@ -127,7 +127,7 @@ end
 
 # ╔═╡ 33ab57f2-4e55-11eb-3b53-89492ca4b5f6
 begin
-	p = plot(legend=:bottomright)
+	p = plot(legend=:bottomright, xlabel="Episodes", ylabel="Sum of rewards during episode")
 	plot!(p, repeated_run(0.5, :SARS, 1000, 500, false), label="QLearning")
 	plot!(p, repeated_run(0.5, :SARSA, 1000, 500, false), label="SARSA")
 	p
@@ -136,7 +136,7 @@ end
 # ╔═╡ a9f81264-4e5b-11eb-2634-cb2179ea9e6b
 begin
 	A = 0.1:0.05:0.95
-	fig_6_3 = plot(;legend=:bottomright)
+	fig_6_3 = plot(;legend=:bottomright, xlabel="α", ylabel="Sum of rewards per episode")
 
 	plot!(fig_6_3, A, [repeated_run(α, :SARS, 100, 100) for α in A], linestyle=:dash ,markershape=:rect, label="Interim Q")
 	plot!(fig_6_3, A, [repeated_run(α, :SARSA, 100, 100) for α in A], linestyle=:dash, markershape=:dtriangle, label="Interim SARSA")

notebooks/Chapter06_Maximization_Bias.jl

@@ -188,16 +188,16 @@ begin
 		run(create_double_Q_agent(), world, StopAfterEpisode(300),hook)
 		push!(DQ_stats, hook.counts)
 	end
-	plot(mean(DQ_stats), legend=:topright, label="double q")
+	plot(mean(DQ_stats)*100, legend=:topright, label="double q", xlabel="Episodes", ylabel="% left actions from A")
 
 	Q_stats = []
 	for _ in 1:1000
 		hook = CountOfLeft()
 		run(create_Q_agent(), world, StopAfterEpisode(300),hook)
 		push!(Q_stats, hook.counts)
 	end
-	plot!(mean(Q_stats), legend=:topright, label="q")
-	hline!([0.05], linestyle=:dash, label="optimal")
+	plot!(mean(Q_stats)*100, legend=:topright, label="q")
+	hline!([5], linestyle=:dash, label="optimal")
 end
 
 # ╔═╡ 00000000-0000-0000-0000-000000000001

notebooks/Chapter07_Random_Walk.jl

@@ -62,7 +62,7 @@ end
 # ╔═╡ 0b1b0448-522b-11eb-0264-9131eabe2525
 begin
 	A = 0.:0.05:1.0
-	p = plot()
+	p = plot(xlabel="α", ylabel="Average RMS error")
 	for n in [2^i for i in 0:9]
 		avg_rms = Float64[]
 		for α in A