Merge pull request #6 from opengm/RC-2.3

getting updates from RC2.3
CombiLP: timeout break visitor issue fixed. External tests required
adding nesterov algorithm
smooth nesterov added
nesterov - more to traansfromation between constraint and unconstraint variables
nesterov - even more to transfromation between constraint and unconstraint variables
Nesterov class updated, parameters added and typedef
Nesterov: code before compiling
nesterov: more compilation bugs fixed
nesterov: compilation errors fixed. Linking errors are pending
nesterov: SumProdTRWS and MaxSumTRWS solvers reused in Nesterov
nesterov: test compiled and runs
nesterov: move bugs fixes
trws_base: minor refactoring for Nesterov
nesterov: marginals reading bug fixed
nesterov: bug in algorithm implementation (acceleration) fixed
add return values of type InferenceTermination
add maxtime to parameter
add definitions for libdai
change strings for boost libraries