add clock to bytecode semantics

(not using it yet though)
start on adding clock to intermediate language
work on updating intLangExtraTheory for clocked intlang
finish updating intLangExtraTheory for clocked intLang
update pmatchTheory for clocked intLang
start on updating exp_to_Cexp_thm1
more exp_to_Cexp_thm1

main App case
more exp_to_Cexp_thm1

up to pmatch case
finish updating toIntLangProofsTheory for clocked intLang
start updating toBytecodeProofsTheory

extend the statement of compile_val for the case when a timeout is
raised. haven't touched proof yet.
work on compile_val

first four cases done
another case of compile_val

the one for (in effect) re-raising timeout exceptions
more compile_val

up to CCall case
tweaked statement and definition

change statement to allow the clock to change, and change definition so
the case split on whether a call is clocked happens later.
started updating proof for new statement.
up to CCall case again

need to tweak jmpbc_thm to allow a Tick before the JumpPtr
work on CCall case

up to last part, showing that the generated bytecode for the call gets
stuck if the semantics says Timeout is raised.
more CCall case, but want to rework statement again

can maybe collapse the two exception cases into one... at the moment the
timeout exception case needs extra hypotheses saying what the stack
looks like in tail position...
finish CCall case (probably)

haven't re-checked the script, but the goal was proved interactively
(gotta go now)
finish all CCall cases of compile_val
finish compile_val