Travis CI: Cache .m2 folder.
add docs to clarify performance of removeFields command
CDK-457. Remove spurious Hadoop snappy native lib check.
Merge pull request #89 from joey/master

CDK-457. Remove spurious Hadoop snappy native lib check.
CDK-367: Look up field position in key for mappings.

This adds KeySchema#position(String) to look up the position of a data
field in the key.
CDK-367: Update entity mapper test for key fields.

This tests that the fields may by out of order, have multiple partition
fields, and may not begin the key.
CDK-472: Add URIPattern#construct to create URIs for patterns.

The URIPattern#construct method takes a map of match data, like what is
produced by URIPattern#match, and produces a URI object that matches the
pattern. This supports constructing URIs that are known to match
patterns without knowing the pattern details. For example, constructing
a dataset URI from a dataset name and a repository URI depends on how
the URI pattern handles the dataset name. For some patterns, it is added
to the path, but some add the name as a query argument. This supports
both cases.
CDK-472: Add Registration support to look up dataset patterns.

This also adds a method to construct a dataset URI from a repo URI and a
dataset name. It should be moved to a URI builder class.
CDK-472: Fix NPE bugs in URIPattern
CDK-472: Add Datasets.URIBuilder

Adds an API for programatic building of Dataset/View URIs.

URIPattern implementation uses LinkedHashMap to preserve order of
options such that pattern.construct() will produce query params in a
predictable order.
CDK-472: Move URIBuilder to spi
CDK-472: JavaDoc and fomatting corrections

* Improved JavaDoc based on comments in https://github.com/kite-sdk/kite/pull/105
* Removed unnecessary whitespace changes in Datasets.java
CDK-453: Add Dataset#getUri.
CDK-453: Add Datasets#repositoryFor.

This adds Datasets.repositoryFor(URI) that returns the repository
responsible for a dataset URI. This makes it no longer necessary to add
the DatasetRepository URI to each DatasetDescriptor, which causes test
problems.
CDK-453: Update dataset input/output format configuration.
Add Copyright to URIBuilder.
CDK-453: Move URI construction into FS repositories.

Some tests were failing because the repository did not have a URI and
could not use it to construct dataset URIs. This moves the repo URI
building into the repository's constructor rather than just using the
builder. This ensures repositories will always have a URI that can be
parsed by URIPattern.
CDK-474: CrunchDatasets takes Dataset or View URI
CDK-474: delay loading Dataset from URI
CDK-451: Add isReady, signalReady to views