Add options for different failure probability levels in CKKS bootstrapping

[andreea-alexandru]

For both uniform ternary and sparse keys, support different values for the number of overflows (leading to different failure probabilities) in CKKS bootstrapping, CKKS functional bootstrapping and scheme switching.

The necessary changes will relate to the Chebyshev coefficients (as the interval and the degree will change) and the corresponding multiplicative depth.