avoiding some synchronization on combineLatest
Merge branch 'master' into combineLatest
Merge branch 'master' into combineLatest
handled combine functions that throw exceptions and added a test against this case
added combineLatest static methods to Observable
Got rid of the last remnants of synchronization in favor of a concurrent map.
Fixed a javadoc parameter.
improved generics for combineLatest (PECS principle)
Tried to adapt according to Ben's review comments.
Merge branch 'combineLatest' of git://github.com/jmhofer/RxJava into pull-267-combineLatest

Conflicts:
	rxjava-core/src/main/java/rx/Observable.java
	rxjava-core/src/main/java/rx/operators/OperationCombineLatest.java
Merge pull request #303 from benjchristensen/pull-267-combineLatest

Pull 267 - Merge combineLatest