implicit problem read arh file instead of dat files
memory error warning in dofvector

added posibility to use est_t_max for time adaptivity. The time error may now be defined as est_t_combined =sum_fac*est_t_sum + max_fac*est_t_max. Default is sum_fac=1 and max_fac=0. Thus, by default adaption is working as before. 

included new variable <lastProcessedTimestep> in AdaptInfo, in order to have the timestep which lead to current time in user program

* Added some headers to AMDiS.h

* Faster serialization of all objects