Allow to use first run simulations for subsequent runs of a given element space

[pedrobcst]

Currently, everytime the analyze function is ran (even if the same paremeters), Xerus will re-simulate, re-query the database. This can be time consuming, and actually makes the sometimes needed iterative process of hyperparameter tuning (ie, g, delta, n_runs, provider settings and so on) time consuming. In light of this problem, the following changes are needed:

• [ ] After the first run, keep track of the already simulated patterns / correlations. (should be almost there..)
• [ ] If this simulations already exist, use them instead of re simulating / re - querying
• [ ] Keep a 'safe' information of simulations / structures that can always be accessed to be used for filtering purposes