Merge pull request #48 from llh1/development

Merge UAT back to development
add Travis CI build
Merge pull request #49 from ke4/55551906_add_ci_build_for_our_applications

add Travis CI build
Add the ability to update the solvent volume through update tube action and update tube rack action
Add specs for updating the solvent volume in the tubes
Bump version to 2.5.2.pre
Call update_tube only if tube_data is a hash
Add doc for updating the tubes in a tube rack with solvent volume
Fix doc
Merge pull request #50 from llh1/55556460_set_volume_for_each_tube_in_update_tube_rack_action

55556460 set volume for each tube in update tube rack action
Add doc for updating a tube with the volume of the solvent
Update index order to be able to use where clause with 'key' only
Add an index on uuid column of items table
Bump version to 1.9.3
Merge pull request #51 from llh1/55878858_fix_search_response_time

55878858 fix search response time
Add indexes on uuid_resources and items tables
Bump version
Fix migrations adding unique index
Merge pull request #52 from llh1/55878858_fix_search_response_time

55878858 fix search response time
[55551906] added Travis CI build