Added new attribute to provide factory function for additional buttons

[ramarivera]

Added a scope attribute, to be executed in the parent scope in order to provide custom buttons, instead of having to stringify a factory function.

When both additionalButtons and "addExtraButtons" are provided, merge both buttons.

[ghiscoding]

Would it be possible to fix the indentation? It's hard to see what you changed when the PR highlight almost everything has changed :(

I think your editor is set to 2 but my code at that time was set to 4 spaces.

[ramarivera]

No problem, I'll try to change it

[ramarivera]

It seems it didn't work. I'll try again later so its easier to spot changes

[ghiscoding]

It might be Tabs not spaces, I used Sublime Text at that time, not sure what was set originally.

If you can't get it to work, I can change my original indentation to 2 spaces. nowadays I'm using VSCode and follow the standard of 2 spaces. So anyway, I could change the indentation if that helps but you might have to redo the PR. Let me know what is best for you, and yes I asked you to change it because I can't see your code change when everything is red :P

[ramarivera]

I think I got it right this time :D

[ghiscoding]

Yes I can see the changes now, thanks for that. Would you mind providing an example with your new buttonFactory and actually I think it might be best to modify the README at the editor extra buttons section with your factory example, that would be great. I assume you tested with and without a factory?

[ramarivera]

I assume you tested with and without a factory?

Unfortunately you assumed wrong :P . I think i fixed it tho.
I'll try to add some examples and an updated readme by the weekend.

[ghiscoding]

Will have to close this PR since support of version 1.x is now over. I'm about to release a new version 2.x that provide supports for Angular 4+

However, if you still need to use it in AngularJS, version 1.1.5 will always be available through NPM, thank you