Keep Multifast Compiled Across Serializations

[0xekez]

Presently, the serialization function only serializes the vector of patterns contained inside a paraglob. For unserializing, a new paraglob is built from that serialized vector of patterns, and its aho-corasick structure is recompiled. This recompilation is expensive though and can take as long as 10 seconds for very long pattern sets.

It would be very nice to be able to serialize a paraglob in such a way that it doesn't need to be recompiled after being unserialized. This is fairly difficult though because of the complexity of the aho-corasick trie inside after it has been compiled and the fact that its memory isn't stored contiguously.