lineVar: allow for lag=0
tets VAR: add cases for lineVar with lag=0
VECM: allow for lag=0 even for const=none
tests VECM: update for lag=0
lineVar: simplify code
myTail: allow further ... arguments
lineVar: allow exogen and lag=0
VECM: code slightly more efficient
tests: reduce digits so that no diff on windows arch
VERSION 0.9-40: update description, and changelog