Make weeksOfMonthByDay match weeks from the end of the month too

[cesarizu]

This PR allows the testing against the week of the month by day from the end of the month, for example the last Friday of the month. This is achieved by passing a negative number to the weeksOfMonthByDay matcher.

[Jean-Rashmir]

Hi cesarizu,
your modification to allow the calculation of last-day of month recurrences works great, however there is a bug related to the daysOfMonth() method as it doesn´t return any recurrences.

I have created a plunkr to illustrate the issue: http://plnkr.co/edit/GUvwbFLAXXwKcGpucP3D?p=preview

(Just exchange the scripts in the head of index.html to see the difference)

[rmckeel]

This is the exact use case I'm interested in - for example the 'last Sunday' of each month from start date to end date. @cesarizu Would love to see a resolve to @Jean-Rashmir 's issue so this can be integrated! Thanks for the great work!

[cesarizu]

@Jean-Rashmir and @rmckeel thanks for your comments. If you use this PR's branch: negative-weeks-of-month-by-day instead of my repo's master branch the plunkr works as expected.

There's an error with my repo's master branch with another unrelated commit (caching results for efficiency, see #52). I'll take a look at that PR asap.

EDIT: I've fix the other PR, so master is working for the plunkr just fine now.

[rmckeel]

I tested locally with the PR's code yesterday, and it worked exactly as desired, fitting the test cases I could think of and keeping the existing functionality I had built with the official branch.

[cesarizu]

@c-trimm I've rebased this branch to the latest master, is there anything else missing or anything you'd like me to do to merge this?

[niftylettuce]

Any update here? This is a core bug otherwise

[Stanton]

Bump