Added some new features and changed from HTML parsing to XML

To summarize what i had done:

### Changed scraping url to rss feed, and nokogori code to parse the rss.

As a consequence of this, rss feed didn't had the MSG counts, so i had to remove it. But it had the date so i required the standart time library and parsed the torrent upload time from UTC to Local time and stored it as :date.

### Added sort/order functionality

Just added '-s' to cli.parse and changed search class's initialize method according to the new options. I just used &sort and &order query parameters of the nyaa's search page.

### Added 's' key feature to open the dorrent in default tracker.

To do this, i made an function which used your download and open functions. I had to make some little changes for this code to work properly.

### Used begin/rescue to main ui drawing loop.

Did this because of the error you get when you ctrl + c out of the program. I just rescued the Interrupted error and it went away.

### Extras

* Changed version
* Edited HELP pages to document the new future.

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Hope you like the changes.