Gav corrections on 0.3.6 (gavofyork#74)

* alpha' dependent on header

* Validator index in assurance extrinsic is encoded as 2 bytes

* Avoid taking log of zero

* Decode the right amount of data

* Fix up function R in PVM Argument Invocation Definition

* Entry points are 0, 5, 10, 15

* Fix Refine lookup case arm

* Numbering.

* Use modern FS shuffle

* Avoid confusion over Work Package's code/codehash

* Invocation: Fix argument order

* PVM Invoctions: Fix Accumulate

* PVM Invocations: Parens

text/pvm_invocations.tex

@@ -154,7 +154,7 @@ \subsection{Accumulate Invocation}\label{sec:accumulateinvocation}
   F(n, \xi, \omega, \mu, (\mathbf{x}, \mathbf{y})) &\equiv \begin{cases}
     G(\Omega_R(\xi, \omega, \mu, \mathbf{x}_\mathbf{s}, s, \delta^\dagger), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{read} \\
     G(\Omega_W(\xi, \omega, \mu, \mathbf{x}_\mathbf{s}), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{write} \\
-    G(\Omega_L(\xi, \omega, \mu, \mathbf{x}_\mathbf{s}), s, \delta^\dagger), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{lookup} \\
+    G(\Omega_L(\xi, \omega, \mu, \mathbf{x}_\mathbf{s}, s, \delta^\dagger), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{lookup} \\
     G(\Omega_G(\xi, \omega, \mu), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{gas} \\
     G(\Omega_I(\xi, \omega, \mu, \mathbf{x}_\mathbf{s}, s, \delta^\dagger), (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{info} \\
     \Omega_E(\xi, \omega, \mu, (\mathbf{x}, \mathbf{y})) &\when n = \mathtt{empower}\\