Updating chemkin module

1. Ignition delay function is now updated to remove nan before
trying to find when did ignition occur

2. Add a function to find first stage ignition delay based
on max of OQOOH species. It can be used to find the time
when peak of any species occured

3. Add a function to find first stage ignition delay based on
inflection in Temperature (WIP) does not work for all conditions
is missing a lot of exception catching for now