Limit of total number of generated (de)serializer

[volauvent]

Currently, there is no limit of the total number of de/serializer classes fast-avro could generate and load during runtime. So, the generated code may saturate the application code cache if there are too many schemas, and it might cause GC issues.

We can set a hard-limit or leverage a LRU cache to limit the maximum number of de/serializer classes that can be loaded during runtime.