Raise error on insert into system collection.

Only if the collection is not system.users or system.indexes.

[ RUBY-492 ]
RUBY-537 fixing behavior of strict, adding deprecation notice
improvement: limiting db#command calls for capped?, cleaning up init
improvement: clean-up of db, lots-o-improvements
Merge pull request #176 from mongodb/raise-error-on-system-insert

Raise error on insert into system collection.
Reverting the collection name check on insert.

[ RUBY-492 ]
RELEASE 1.8.4.rc0
minor: adding license to gemspecs to get rid of warning
RUBY-567 cast VALUE to char * to avoid warning
minor: removing rvm gem, package task can't be automagic anymore since we combined bson.gemspec
minor: fixing deprecation notice in the docs
minor: changes to deploy rake tasks
RELEASE 1.8.4
minor: more fixes to deploy scripts
minor: remove puts
minor: whitespace in ordered_hash.rb
RUBY-535 replace #clone with #initialize_copy
minor: adding deprecation notice for strict to readme
RUBY-570 removing test files from gemspec (for now)

The structure of our combined test suite doesn't allow it to be separated out easily so that it can be included with each gem in our repository (specifically, the test_helper).

Since you can't actually run these test files we've been inlcuding in our gemspec, I'm removing them for now. Long term after ruby-bson 2.0 is released the bson gem should include a runnable test suite in the release verison.

This change does two things:

- Removes non-functional test files from bson.gemspec
- Removes bson test suite from mongo.gemspec
RUBY-576 documentation fix for ensure index

- Syntax correction for Collection#ensure_index examples.
- Added Ruby 1.8 and Ruby 1.9 examples for Collection#create_index.