test for project and group array
more test for group and project
fongorule
project must not handle array
Merge branch 'minmax' into aggregaremore
try to add keyword
add ExpectedMongoException for simplification
apply/unapply.. ugly, must refactor
can create named db and collection in test
handle $concat and $strcasecmp but break $project
$ifNull
todo
Merge branch 'master' into aggregatemore

Conflicts:
	src/main/java/com/mongodb/FongoDBCollection.java
	src/test/java/com/foursquare/fongo/FongoIndexTest.java
correct message
koErrorResult -> notOkErrorResult
merge from master
add $subtr
add $cmp
add $toUpper and $toLower
cleanup