Upgrade to Ruby 1.9 hash syntax. Not a problem since this gem requires Mongoid >= 3.0.0, which itself requires Ruby 1.9
Remove comment mentioning :default_type option, which appears no where in the code.
Convert string-based class eval syntax to block based. This is safer and more readable.
Enable pass-thru of all valid options to Mongoid field method
Easier to read syntax
Support aliased Mongoid fields with options[:as] parameter. The options[:field] paramter is no longer externally accessible.

For example:

taggable :t, as: tags

Will store the tags array in a database field 't', but all it's methods will use the names tags, e.g. 'tags_string', etc. This works because :as is delegated to Mongoid, which uses this alias feature.

This is useful to reduce storage size in MongoDB.

This commit includes some other trivial changes (TAGGABLE_DEFAULT_SEPARATOR is now DEFAULT_SEPARATOR)
Update to Readme
Remove variable which is now irrelevant
Better syntax
move :tags to DEFAULT_FIELD constant
D'oh typo in documentation
Bump version to 1.1.0 and cleanup versioning:
- Move version to a class file
- Reference version in Rakefile
- Regenerate Gemspec
- Remove :string_method option.
- Add #tags_string_for(context) instance method.
- Throw error if either :field or :string_method options are set; these have been removed as of version 1.1.0.

The reason for removing string method is that we automatically define "tags_tagged_with", "tags_separator", etc. with hardcoded names.

If the user wants a custom string method, they can do either of the following:

```ruby
alias :my_string_method :artists_string
```

OR

```ruby
def my_string_method
  tags_string_for(artists)
end
```
- Get rid of all instance-to-class delegation. This is unnecessary/redundant.
- Remove trivial methods #convert_string_to_array, #clean_up_array and replace with a single "format_tags_for(context, value)" method to take care of this.
- Remove trivial method #convert_array_to_string. Same as Array#join
- raise InvalidTagsFormat error if attempting to set tags to something other than an Array or String
Remove ability to change tag separator after initialization. I doubt any one actually uses this feature, but if they do it's very dangerous! If someone needs a more complex string separator method, its easy to build using tags.join/split(magic_separator()).
Merge pull request #8 from johnnyshields/master

Code cleanup + Mongoid options pass-thru