Fix/Suppress remaining Cppcheck warnings (#291)

Fix/suppress the following cppcheck warnings:

* arithOperationsOnVoidPointer
* uninitMember
* const*
* shadowVariable
* assignmentIntegerToAddress
* containerOutOfBounds
* pointer-related warnings in Ragel source
* missingOverride
* memleak
* knownConditionTrueFalse
* noExplicitConstructor
* invalidPrintfArgType_sint
* useStlAlgorithm
* cstyleCast
* clarifyCondition
* VSX-related cstyleCast
* unsignedLessThanZero 

Furthermore, we added a suppression list to be used, which also includes the following:
* missingIncludeSystem
* missingInclude
* unmatchedSuppression

src/som/slot_manager_dump.cpp

@@ -82,6 +82,7 @@ void dumpSomSlotManager(const SomSlotManager &ssm, const Grey &grey) {
             fprintf(f, "\t shared reset (users = %zu)\n", ir.entries.size());
         } else if (contains(by_slot, i)) {
             const SlotCacheEntry &ce = *by_slot.at(i);
+            // cppcheck-suppress knownConditionTrueFalse
             if (ce.parent_slot != SomSlotManager::NO_PARENT) {
                 fprintf(f, "\tparent:%u", ce.parent_slot);
             }