Basic take-while implementation
TakeWhile support for predicate with index
Unit tests for take while
Restored javadoc
Renamed takeWhile with Func2 parameter to takeWhileWithIndex

Added takeWhile and takeWhileWithIndex methods to Observable
play with tests in clojure -- still not hooked up or actual tests
javadocs
merge Operator TakeWhile pull request

This is a manual merge of https://github.com/Netflix/RxJava/pull/125 contributed by @mairbek
Merge pull request #146 from benjchristensen/issue-87

Merge of Pull #125 for Issue #87 Operator TakeWhile