Add constants for case insensitive searching
Patch Arel to give the search logic
Make true and false predicates accept false values

This will make all boolean predicates more consistent.
Support merging joins across searches using a shared context

When merging search criteria, it's necessary to use the same join
dependency with a shared alias tracker. This can be achieved by passing
a context option when building Search objects.

Rails 3.0: use Model.joins(context.join_associations) to merge relations
with JoinAssociations.

Since Rails 3.1: can use Model.joins(context.join_sources) to merge
relations with Arel::Join nodes.

Since Rails 4.1: only context.join_sources is available as Arel,
context.join_associations stops being supported.
Merge pull request #412 from avit/shared-context

Support merging searches using shared context
Update README regarding changed I18n in Rails 4.2

[skip ci]
README fixes [skip ci]
Update Gemfile
Update ransack.gemspec
Update .travis.yml
Use the new Docker queue

and don't install Bundler, it's already installed
Merge pull request #420 from joshk/patch-1

Use the new Docker queue
Update the README now that Rails 4.2.beta is out

and remove the no longer needed section about the I18n placeholder
change in Rails 4.2, which was reverted.
Release version 1.3.0

Additions:
- search scopes by popular demand
- JOINS merging
- OR grouping on base search
- authorizations for attributes, associations and scopes
- improved boolean predicates’ handling of false values
- allow configuring to raise on or ignore unknown search conditions
- allow passing blank values to search without crash
- wildcard escaping compatibility for SQL Server databases
- various I18n translations
Merge pull request #409 from PChambino/accept_false_in_true_and_false_predicates

Make true and false predicates accept false values
Merge pull request #405 from Kartstig/master

Fixes #82 Case Insensitive Searching
Follow-up to #405: rename case insensitive queries

icon => i_cont
inot_cont => i_not_cont
Revert #405 Arel patching due to regression

“lib/ransack/adapters/active_record/compat.rb:24:in
`<module:Visitors>': superclass mismatch for class ToSql (TypeError)”
Search.new and the ransack scope no longer modify the params hash

Closes #378.
Add not_true and not_false predicates