Changes the behaviour of `MultipleFactory` and implements build speed overrides.

[CCHyper]

Closes #106, Closes #656, Closes #657, Closes #658, Closes #659

This pull request covers multiple related items;

• Changes the effect of the MultipleFactory bonus to be the same as Red Alert 2 when calculating an object's build time. Now, this is a straight discount multiplier that is cumulative.

• [TechnoTypes] BuildTimeMultiplier=<float> Multiplier to the time it takes for an object to be built. Defaults to 1.0.

• [General] (RULES.INI) LowPowerPenaltyModifier=<float> The "double penalty" or "half penalty". Multiply this by the power units you are short of to get the actual penalty to the build speed. Defaults to 1.0.

• WorstLowPowerBuildRateCoefficient and BestLowPowerBuildRateCoefficient now have an effect on the production times when in a low power state. Previously there were not used.

• [General] (RULES.INI) MultipleFactoryCap=<integer> The maximum number of factories that can be considered when calculating the multiple factory bonus on an object's build time. Defaults to 0 (no limit).