remove logfile spew
add debug print to the assert

New moses is now asserting.  We need a unit test for this :-(
quiet down more logfile spew
add default ctor for feat sel params
bugfix: std::next() will iterate past end()

The std::next() does not know where sf_pop.end() is, and, so if
told to go beyond it, it will; leading to garbage/junk.  Then
sf_pop.erase() will erase everything, leading to an empty population
and a crash.
MOSES: Minor cleanup.
MOSES: restore some of logging previously killed.

Actually, it could be useful, and is not that verbose.
MOSES: change diversity_cap to size_t

This avoids a compiler warning. Anyway, negative values don't make
sense, so there's no point in using a signed int.
MOSES: more log file cleanup.

I changed these back to info() from debug(). Its mostly not too verbose.
Merge pull request #166 from linas/moses

Moses bug fix