dual index refinements

ensure max length of "Index" used by MiSeq is the split dual indexs' size,
and use custom default_expected_tag in preference to Index{,2} when using
samplesheet as source of LIMS info
ensure samplesheet test works without WTSI filesystem present
Merge branch 'devel' of github.com:wtsi-npg/npg_tracking into devel2

Conflicts:
	Changes
Merge pull request #190 from dkj/wtsi_free_samplesheet_test

WTSI free samplesheet test
Travis CI configuration and associated changes
attempt to patch intermittently failing test: retrieve time after it was updated
Merge pull request #191 from mgcam/travis_ci

Travis CI configuration and associated changes
Merge remote-tracking branch 'wtsi-npg/devel' into dual_index

Conflicts:
	Changes
Merge pull request #175 from dkj/dual_index

Dual index - refinements
Change reference name and location
Merge pull request #192 from KateTaylor/reference_name_changes

Change reference name and location
Review comments
wrapper object for the status and a script to write status to a file
use DateTime object to generate timestamp since it is known how to make it work consistently across hosts; update build file
Full directory path in PHIX_ROOT
Full filename in PHIX_FILE
Merge pull request #193 from KateTaylor/reference_name_changes

Review comments
make logic reader-friendly, fix spelling, add test data files to MANIFEST, to fix test Travis failure make dependency of json serialization on JSON::Any explicit
npg dev url is set to the url of the dev server that is actually used for API calls; psd next release dev url replaced with training url, RT#412417
fix one more expected url in tests