Removed deprecated set_table_name set_primary_key set_sequence_name methods

Version 1.5 and later support Rails 4. These methods already deprecated.
See http://guides.rubyonrails.org/3_2_release_notes.html
"8.1 Deprecations"
Merge pull request #364 from yahonda/remove_deprecated_set_sequence_name

Removed deprecated methods from unit tests
Update README to support assignment methods
Merge pull request #365 from yahonda/update_readme_for_deprecated_methods

Update README to support assignment methods
Remove add_limit_offset! method from Oracle enhanced adapter
ActiveRecord 3.x and later version uses Arel for this SQL generation

It should not backport to release14 branch which supports Rails 2.3
Merge pull request #369 from yahonda/remove_unused_add_limit_offset

Remove add_limit_offset! method from Oracle enhanced adapter
Update Gemfile to use `bundle config --local`

example
$ bundle config local.activerecord /path/to/rails
Merge pull request #370 from yahonda/update_gemfile

Update Gemfile to use `bundle config --local`
Change OracleEnhancedOCIConnection#describe logic

Background:

  Some time ago, while running migrations and test schema preparations on one of internal Oracle setups,
    job wallclock times increased dramatically (in order of 10x). After some investigation it became
    apparent that problem was in OracleEnhancedSchemaStatements::create_table method - it took 40+ seconds to
    execute OracleEnhancedAdapter::table_exists? which itself is wrapper for OracleEnhancedOCIConnection::describe
    Though most probably, the time increase isn't directly related to ruby-oci8 or oracle-enhanced, as same problem
    was replicated in SQL Developer (which internally also translates 'DESC[RIBE]' to UNIONed SELECT), and is due
    to DB configuration/patches/size increases, current gem code can be improved a bit/this provides solution for
    this isolated performance drop.

Proposal:

  When using OCI8 interface and calling #describe on non-existant table (as is probably the most frequent case in
    test DB preparations and migrations), oracle-enhanced should not retry describe via SELECT-based `super` when no db link
    is specified and OCIException code is 4043 (object does not exist)

Signed-off-by: Aleksandrs Ļedovskis <aleksandrs@ledovskis.lv>
Merge pull request #375 from aledovsky/bug/oci8_describe_non_existant

Change OracleEnhancedOCIConnection#describe logic
Support `remove_columns`

`def remove_columns(table_name, *column_names)` is defined
in ActiveRecord::ConnectionAdapters::SchemaStatements, which does not
require Oracle enhanced specific implementation.

`def remove_column(table_name, column_name, type = nil, options = {})`
ignores `type` and `options` arguments to avoid ORA-00904 errors

See rails/rails#8267 for Rails change.
This commit should not backport into release14 branch.
Merge pull request #377 from yahonda/support_remove_columns

Support `remove_columns`
Order view output alphabetically
Add `FORCE` option at `CREATE OR REPLACE VIEW` in structure_dump_db_stored_code
because it is quite difficult to dump views to satisfy dependencies.

Views created with FORCE option may be invalid,
which should be implicitly recompiled at the first time they are used.
Merge pull request #378 from yahonda/pr372_sandbox

Dump views output alphabetically and FORCE option
Update History.md for 1.5.1
Merge pull request #380 from yahonda/prepare_relese151

Update History.md for 1.5.1
Release 1.5.1
Use default tablespace for primary & foreign key constraints defined during table creation
Support schema option in database config