ARROW-201: [C++] Initial ParquetWriter implementation

[xhochy]

No description provided.

[xhochy]

Also with this PR comes read support for max_definition_level = 1.

[wesm]

In testing more data types, we may wish to use templates and parameterized test cases to enable more code reuse

[wesm]

Finished reviewing -- looking good. Nice to get these first end-to-end tests working, so that we can then add the rest of the data types (and other missing features, e.g. compression) and work on read/write performance

[xhochy]

Incorporated all comments, travis builds seem to be breaking in an unrelated manner.

What's missing is the initial check if we really have a flat column. Therefore I would need its definition.

[xhochy]

Rebased and now also Travis is happy.

[wesm]

A column is flat if:

• max repetition level is 0
• for REQUIRED field, max def level is 0, for OPTIONAL the max def level is 1

does that seem right?

might be worth having a helper function for this

[xhochy]

We now also have a check for a flat column.

I also wanted to add some DCHECKs (not needed for a merge but I like have code with assertions) but I get the following error if I added it somewhere in src/arrow/parquet/reader.cc:

error: ‘arrow::parquet::internal’ has not been declared

[wesm]

looks good, +1. let's look into the namespace issue in arrow/util/logging.h separately