[isabelle-dev] Clarified timeouts for Isabelle/ML tools

[Makarius]

*** General ***

* Timeouts for Isabelle/ML tools are subject to system option
"timeout_scale" --- this already used for the overall session build
process before, and allows to adapt to slow machines. The underlying
Timeout.apply in Isabelle/ML treats an original timeout specification 0
as no timeout; before it meant immediate timeout. Rare INCOMPATIBILITY
in boundary cases.


This refers to Isabelle/3b5196dac4c8.

Application: smt_timeout = 0 (unlimited) in Isabelle/f3378101f555.


	Makarius