Remove Validation section whose content can be found on the wiki

src/docs/chapter/user/20_Validation/ProB_Validation_Methods.adoc

-
-[[prob-validation-methods]]
-= ProB Validation Methods
-
-ProB offers various validation techniques:
-
-* <<consistency-checking,Consistency Checking (Finding Invariant
-Violations using the Model Checker)>>
-* <<constraint-based-checking,Constraint Based Checking>>
-* <<refinement-checking,Refinement Checking>>
-* <<ltl-model-checking,LTL Model Checking>>
-* <<bounded-model-checking,Bounded Model Checking>>
-
-Here we want to describe the advantages and disadvantages of the various
-methods.
-
-.__Comparing ProB Validation Techniques__
-[cols=",,,,",options="header",]
-|=======================================================================
-|Question |Model Checking |LTL Model Checking |CBC Checking |Bounded
-Model Checking
-|Can find Invariant Violations ? |yes |yes (`G{INV}`) |yes |yes
-
-|Only reachable counter-examples from initial state? |yes |yes |no |yes
-
-|Search Technique for counter-examples? |mixed df/bf, df, bf
-|depth-first (df) |length 1 |breadth-first (bf)
-
-|Can deal with large branching factor? |no |no |yes |yes
-
-|Can find deep counter-examples? |yes |yes |n/a (length 1) |no
-
-|Can find deadlocks ? |yes |yes (`G not(deadlock)`) |yes |not yet
-
-|Can find assertion violations ? |yes |(`G{ASS}`) |static |no
-
-|Can confirm absence of errors ? |finite statespace |finite statespace
-|invariant strong enough |bound on trace length
-|=======================================================================

src/docs/chapter/user/20_Validation/Refinement_Checking.adoc

-
-[[refinement-checking]]
-= Refinement Checking
-
-ProB can be used for refinement checking
-of B, Z and CSP specifications. Below we first discuss refinement
-checking for B machines. There is a tutorial on checking CSP assertions
-in ProB which can be viewed
-http://stups.hhu.de/ProB/w/Checking_CSP_Assertions[here].
-
-[[what-kind-of-refinement-is-checked]]
-== What kind of refinement is checked?
-
-ProB checks trace refinement. In other words, it checks whether every
-trace (consisting of executed operations with their parameter values and
-return values) of a refinement machine can also be performed by the
-abstract specification.
-
-Hence, ProB does *not* check the gluing invariant. Also, PRE-conditions
-are treated as SELECT and PRE-conditions of the abstract machine are
-*not* always propagated down to the refinement machine. Hence,
-refinement checking has to be used with care for classical B machines,
-but it is well suited for EventB-style machines.
-
-[[how-does-it-work-refinement-checking]]
-== How does it work?
-
-1.  Open the abstract specification, explore its state space (e.g.,using
-an exhaustive temporal model check).
-2.  Use the command "Save state for later refinement check" in the _Verify_ menu.
-3.  Open the refinement machine.
-4.  You can now use the "Refinement Check..." command in the _Verify_ menu.

src/docs/chapter/user/20_Validation/ZZ_section_footer.adoc

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