Fixes some whitespace issues.
EXP-460. Update Express to use Provider framework for KijiTableInputFormat from KIJIMR-288

issue: https://jira.kiji.org/browse/EXP-460
review: https://review.kiji.org/r/1973
EXP-464. Update dead dependency on kiji-schema 1.5.1-SNAPSHOT

issue: https://jira.kiji.org/browse/EXP-464
review: https://review.kiji.org/r/1990
POM-40. Require JDK 7 to compile Kiji projects

issue: https://jira.kiji.org/browse/POM-40
review: https://review.kiji.org/r/2007
EXP-451. Express flow steps dont always start on YARN

Revamp express.py
 - Drop dependency on python-base:
   - use argparse
   - copy logging setup from python-base
 - Normalize classpath entries:
   - Normalize to absolute real paths (no symlinks)
   - Remove duplicates (by path name)
   - Remove classpath entries that do not exist
 - Add unit-tests for classpath normalization.

issue: https://jira.kiji.org/browse/EXP-451
review: https://review.kiji.org/r/2038
EXP-466. Minor bugs in express.py's calculation of java options and dist cache path

issue: https://jira.kiji.org/browse/EXP-466
review: https://review.kiji.org/r/2047
EXP-467. Jobs launched with express.py on CDH 5 die with "Caused by: java.lang.ClassNotFoundException: Class cascading.tap.hadoop.io.MultiInputSplit not found" in child processes

Expand the scope of JARs included on the distributed cache.

issue: https://jira.kiji.org/browse/EXP-467
review: https://review.kiji.org/r/2048
EXP-463. express.py script should exit with non-zero exit code if the command fails

Make sure subprocess exit codes are correctly propagated.

issue: https://jira.kiji.org/browse/EXP-463
review: https://review.kiji.org/r/2049
Merge remote-tracking branch 'upstream/master'