SCHEMA-354. Initial compatibility with HBase 0.94.

This patch allows KijiSchema to pass tests with unit tests run as integration
tests against a live HBase 0.94 cluster.

Until POM-14 and FAKEHBASE-17 are included, we cannot build against HBase 0.94
directly; SCHEMA-353 tracks the total work to upgrade to HBase 0.94 while
retaining 0.92 support.

This patch does the following:

* HBase ColumnPaginationFilter is only used to trim data requests for columns
  with maxVersions=1; unlike in 0.92, HBase 0.94 will ignore the limit parameter
  and yield at most one element. Some columns in data requests with varying
  per-column maxVersions parameters may return more data than before (but never
  less than the user requested).
** KijiPaginationFilter moved to impl package, contract revised.
** Usage of KijiPaginationFilter restricted to internal cases.
* Get pagination tests working on 0.94.
** Other test cases revised to conform to requirements for KijiClientTest
   portability.
* Fix incorrect HBaseDataRequestAdapter tests.
** The filter lists being tested were simply incorrect. I do not believe
   that HBase 0.92 printed filter lists in Get.toString() or Scan.toString().
   HBase 0.94 causes stricter checking.
* KijiDataRequestBuilder maintains stable iteration order.
  Columns in KijiDataRequests built by KijiDataRequestBuilder now
  iterate in a stable order, guaranteeing that HBaseDataRequestAdapter
  constructs Gets/Scans (and their associated filters) in a stable order
  so that TestHBaseDataRequestAdapter passes.
* Disable unnecessary hbase-maven-plugin in kiji-schema-extras.
  There are no integration tests for this module; don't waste time on this.

** all kiji-schema tests pass when run on an HBase 0.94 cluster **
The following test plan succeeds:

  mvn clean verify -Dkiji.test.cluster.uri=kiji://localhost:2181/ \
      -Dorg.kiji.schema.KijiClientTest.HBASE_ADDRESS=localhost:2181

  mvn clean verify # Succeeds using 0.92 and Fake HBase