Changes

Summary

1. more direct elapsed run_time via bash_process wrapper (via Scala and C);
2. merged
3. use SystemOnTPTP.list_systems from Isabelle/Scala, with dynamic URL option and more elementary error messages;
4. clarified signature: let Sledgehammer handle SystemOnTPTP comments;
5. clarified signature: url may change dynamically and is part of result;
6. clarified error;
7. support timeout, similar to perl LWP::UserAgent;
8. clarified signature;
9. tuned;
10. clarified signature: function_thread is determined in Isabelle/Scala, not Isabelle/ML;
11. support for SystemOnTPTP in Isabelle/ML and Isabelle/Scala (without perl);
12. clarified HTTP.Content: support encoding; more realistic HTTP.Client operations;
13. clarified signature: more explicit HTTP operations;
14. tuned;
15. more robust;
16. clarified signature;
17. clarified components;