** updates
- replace old adaptive rejection sampling (ARS) code with adaptive rejection metropolis hastings sampling algorithm (ARMS) code by Wally Gilks, which is more robust and efficient.
- add new function
SAEM_mirt()of MIRT estimation with stochastic approximation (Polyak-Rupper Averaging) - add new function
SOE_mirt()which employs a special prior so that$theta$ has posterior normal distribution
- fix cran comments: provide toy examples to be quickly executed by user in less than 5 sec for each Rd file
- small modification to StEM_mirt() function: set minimum burn-in step size to be TT=20 by default
- small modification to StEM_pcirt() function: set minimum burn-in step size to be TT=20 by default
- fix Step output bug: Step start from 1 instead of 0
- update version number to 1.2
- update Github repository link
- update Travis-CI icon
- add BugReport link