Initial support for a Rails 4.2 beta testing environment

Conflicts:
	runspecs
Reworked foreign key support for ActiveRecord 4.0, 4.1 and 4.2
First steps towards defaults support for AR 4.2
Fix column spec failure for 4.2
Fix schema dumper for 4.2 specific default functions
Update .travis.yml file
mysql_adapter reverse_foreign_keys method refactoring
Include VisitTableDefinition module to AbstractMysqlAdapter
Fix version inside condition
Fix index options issue
Index options fix
Fix revert of add_foreign_key
Merge pull request #186 from SPBTV/rails-4.2

Rails 4.2 Support
upgrade to schema_dev 1.1, add rails 4.2
note rails 4.2 has :index option to column
normalize index options before use — in particular before use by AR
fix bad merge — referring to a variable that no longer exists
quite some warnings due to uninitialized variable @too_many
normalize column options in command recorder
Merge branch 'master' into rails-4.2

Conflicts:
	.travis.yml
	gemfiles/rails-4.2/Gemfile.base
	gemfiles/rails-4.2/Gemfile.mysql2
	gemfiles/rails-4.2/Gemfile.postgresql
	gemfiles/rails-4.2/Gemfile.sqlite3
	schema_plus.gemspec