fix stdin message handling & specs

closes #1386
Pass correct HOME env into chroot

Without this patch the logstash isn't able to start on Debian 7 when using file input, as both HOME and SINCEDB_DIR aren't set in chroot.
Merge branch 'pr/1343'
closes #1343
initial spec for pipe input

removed logging

fixed encoding header

closes 1385
replace json parsers with JrJackson and Oj
refactored timestamps with new Timestamp class
closes #1434
fix external command invocation
changelog for 1.4.2
Fix missing require
Fix typo
Fix for #1451

Line codec was using an undefined variable which casued it to throw and exception.

Fixed and added tests for line codes

Closes #1451
Squash extra lines
Verify method is getting called
Reference github issues now.

Hosted Jira (logstash.jira.com) is currently busted because we have
exceeded the maximum number of users that platform can accomodate
(according to Atlassian support). Until that is resolved, let's point
everyone at github issues instead.

closes #1508
Add tests to cover codec autoswitch for stdin + tcp inputs

json->json_lines & plain->line

Tests for #1392
Closes #1394