MINOR: filters: Add instance parsers for the built-in classes

MINOR: filters: Add instance parsers for the built-in classes

Connect built-in classes to parsers that produce a instance's flt_conf
without attaching it to the legacy evaluation list.

Provide a bridge to legacy keyword parsers, translating the stored argument
vector to their empty-string-terminated convention and rejecting leftover
arguments. Use it for trace, bandwidth limitation, SPOE and Lua; restore
curproxy around SPOE parsing and resolve Lua filters by instance id.

Use dedicated parsers for cache, FCGI, compression and decompression so
their legacy implicit/explicit reconciliation does not modify
filter_configs.  Cache and FCGI application names are supplied by the
instance identifier.  The filter-config directive and instance finalization
follow separately.