Add support for determining/filtering symbol tables

[ikelos]

Issue #985 will not work with versions of symbol tables generated by dwarf2json older than a particular version. We therefore need to add support to filter (either as part of a SymbolTableRequirement or manually) to filter out/fail on symbol tables that have metadata that matches the broken versions.

[ikelos]

This is probably going to get implemented as a check on specific symbol tables as requested by the plugin through a method on symbol_space, specifying metadata criteria required, which will then throw an exception if the criteria aren't met. See #1066 for more discussion.