separate scanner lib, so that it can be used from cmd line.

e.g. from out directory:
cat ../test/scala/lms/tutorial/scannerlib.scala query_t1gram2.check.scala query.scala >run.scala
scalac run.scala
scala scala.lms.tutorial.query ../data/t1gram.csv

time scala scala.lms.tutorial.query ~/Downloads/googlebooks-eng-all-1gram-20120701-a
real     1m24.755s
user     1m19.490s
sys      0m1.489s

btw,
wc -l ~/Downloads/googlebooks-eng-all-1gram-20120701-a
 86618505 /Users/namin/Downloads/googlebooks-eng-all-1gram-20120701-a