This commit adds new "--inspect-wait" flag which works similarly
to "--inspect-brk" in that it waits for inspector session to be
established before running code. However it doesn't break on the first
statement of user code, but instead runs it as soon as a session
is established.
Currently runtime exception are only displayed at the program end in
terminal, which makes it only a partial fix, as a full fix requires
https://github.com/denoland/rusty_v8/pull/1149 which adds new bindings
to the inspector that allows to notify it about thrown exceptions.
This will be handled in a follow up commit.
