Update README.md: Removed outdated parts
Added tutorial for Nokia X
Modified proguard-project.txt to work with Nokia X
Renamed Nokia X to Nokia IAP
Merge pull request #183 from nokia-developer/master

Nokia IAP tutorial
Update README.md - testing with Nokia Store
Fixed issue where buying without SIM card cases NPE.
Added "No SIM" to getResponseDesc.
Revert "Added "No SIM" to getResponseDesc."

This reverts commit 72c9c00ffd6185ccc285de2f513925981220dd6c.
Now handles RESULT_NO_SIM response code.
Updated headers.
Merge pull request #186 from nokia-developer/master

Nokia: Fix for issue when buying without SIM card causes NPE