Add continuous observation to the Normal distribution
Add Continuous trait for observations on continuous distributions + add logp for Beta, Exponential, Gamma, Normal and Uniform distributions
Remove unnecessary deactivate() and activate() functions
Add continuous logp to Dirichlet distribution + add bound function
Remove Continuous trait for Atomic classes
Merge branch 'dev-#287' of https://github.com/Synapski/figaro into Synapski-dev-#287
Merge branch 'Synapski-dev-#287' into DEV2.5.0