Iranian Presidential Election Means Nothing
Remember, Iran is not a democracy, it's a theocracy. It's constitution says that it must be ruled by the will of Allah, but since Allah of course never appears (Since he doesn't exist....), it is up to Supreme Leader Ayatollah Khamenei to interpret what the will of Allah is. That means that he can overrule all decisions by the President and the Parliament and has the final say on all issues.
The President is thus in Iran not really a decision maker, he is more of a bureaucrat in charge of administrative and representative tasks. As such, he has almost no power, meaning that the oppressive terrorism supporting ways of the Iranian government won't change even if that is what Rohwani would have wanted.
What his election does indicate is however that there is increasing popular discontent with the clerical regime. In part because of sanctions imposed on Iran because of its suspected nuclear weapons programme and in part because of irrational economic policies, the Iranian economy is nose-diving, creating widespread economic hardship among the people. Meanwhile, much of the money the government still has is being diverted in to supporting Hezbollah in Lebanon and the Assad regime in Syria. Unlike Ayatollah Khamenei, most Iranians care more about putting food on their table than propping up the Assad regime, so they choose to express their discontent by electing Rohwani.
Unfortunately, the will of the people, and Rohwani, will in a theocracy take a back seat to the will of the alleged voice of Allah, Ayatollah Khamenei.