use java7 to run secor processes by default
refactor to share the logic to determine which java to use
MessagePack parser with unit tests.

Want to do some more manual testing and add a couple more tests.
Merge pull request #45 from zackdever/msgpack-parser

MessagePack parser
Update contributors list
Merge pull request #50 from zackdever/contributor-update

Update contributors list
make sure that we use bash shell
Merge pull request #49 from yswu/yswu_java7

use java7 to run secor processes by default
pass in the codec to the verifier for delimited text reader
Merge pull request #53 from lefthandmagic/delimitedtext_test_fix

pass in the codec to the verifier for delimited text reader
Convert LogFilePath constructor to a create method

The previous constructor didn’t really fit in with the other constructors
and felt a bit misplaced. It’s now been converted to a static method,
#createFromPath, that does all the path parsing and then simply returns
a new LogFilePath object.
Make it possible to override log filenames

This is sort of a work in progress, and so far all existing code has
been ported to using `Partitions` objects rather than simple String
arrays. While I’m all for keeping it simple, using arrays all over the
place will make the code more complex than needed.
Add helper methods for formatting of `Partitions`
Refactor LogFilePath constructor
Move private method in LogFilePath
Always include offset as last filename component
Always include Kafka partition in filename
Add support for custom delimiters in log filenames
Stray delimiters