Just General Questions

CodeIgniter is "just" a framework, so it's helping you while programming your application. It offers a few standard functions, that makes your life soo much easier, when coding in PHP.
I think it's absoluty worth trying out, since it gives you the opportunity to write clean code, after a nice pattern (MVC).
To answer your question, yes you can use CI for something like that, but you have to accept that CI won't give you everything, but still a lot.
And yes, CI is, just like most other frameworks, to make your PHP life easier. 
I personally think CI is good, because it's not as big and complex as some other frameworks, and you can make the best out of it, if you have a little bit of knowledge about CI (as well as of PHP).
A good starting point would be the documentation.

Go for it, it's not to hard if you understood the concept of CI!  

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