Improved input type inference, bug fixing, code simplification

This closes #176
[FLINK-1235] Compiler accepts iterations referenced from the static path of other iterations
 - Fix NepheleJobGraphGenerator to support iterations referenced on the static path of another iteration
 - Catch nested iterations on dynamic path properly in optimizer (and give a good error message)
[FLINK-1226] Add API support for passing Configurations to InputFormats

This closes #196
[FLINK-1230] Add documentation and an example for collection-based execution

This closes #195
[FLINK-1221] Use the source line as the default operator name

This closes #197.
[streaming] Removed obsolete Join example
[FLINK-1204] [streaming] Individual, self-contained packaging for streaming examples
[streaming] StreamExecutionEnvironment rework + user class loader fix for cluster deployment
[streaming] Example cleanup + windowJoin fix
[streaming] Examples refactor and packaging update