[Matlab/Examples] Make constant pressure reactor example more explicit
[Matlab/Examples] Make constant pressure reactor example more explicit

Both the reactor and the adjacent reservoir need to have the same pressure. This
example relied on the fact that the default pressure of the 'air' phase is 1
atm, which caused it to break if the user changed the pressure of the reactor
gas.

git-svn-id: e76dbe14710aecee1ad27675521492cea2578c83@2476 02a645c2-efd0-11dd-984d-ab748d24aa7e

Cantera/cantera-svn,Cantera/cantera-svn,Cantera/cantera-svn,Cantera/cantera-svn,Cantera/cantera-svn,Cantera/cantera-svn