fix match token-level condition: immediately terminate and return empty match result when curr pos is outside sent

This reflects the fact that positions stored in matches are
absolute positions, while Position type is used in the
language as position relative to current position in the
sentence context. So mixing the two was confusing at the very least.
This also actually fits the most recent version of spec,
which no longer mentions Position, either.

longest() and oneof() operator takes boost::shared_ptr<std::vector<boost::shared_ptr<ConjConditions> > >

1) MatchOperator was essentially a wrapper for "match" section of "apply" operator
2) Other operators like Repeat actually used ConjConditions directly, without using MatchOperator
   - so ApplyOperator could too!
3) The confusion was about "match" referring both to part that is matching
   sentence against match conditions, and the results of this matching process.
   That led e.g. to "match_operator" rule in grammar, which was unlike
   "strset_operator" rule and the like. "match_operator" was about
   the "match" section in "apply" and now it is more straightforward.
   Next step should rename "match_fit" to be actual "match_operator",
   consistent with "XXX_operator" for other XXX types.

fix crashes in markmatch / unmarkmatch caused by taking a reference to a shared pointer instead of just making a copy, and a typo

MatchVector, AnnotationMatch, TokenMatch are now MatchData
MatchData is value_type of Match which now has get_value/set_value
Match has also copy construction working properly now
Default value for Match holds MatchVector so adding $m:_M var in grammar works as intended.

A condition that repeateadly matches an array of conditions returning resulting vector of vectors.

MatchResult - change constructor so when you provide Match it defaults to matched = true.
TokenCondition - be a bit defensive about possibility of inner predicates changing $_