Fix grammar for Codes Meanings

Not sure if it's OK to change "It is" to "There are" but there are some cases where it can't be avoided. What do you thinkg?
Changes based on suggestions

You were so positive about my changes that I went a little deeper.
I couldn't change to the suggested "raining fucking heavily" because then I would have to change almost every line, and some of the humor comes from the contrast of detaching the adjective from the noun. I like the fact that it sounds kind of computer-generated by following a few rules, but really, it's just strings.
Changed "clear outside" to "awesome outside" 
I was thinking of changing "moderately" to "kind of" or "kinda" but that would change the computery nature of it.
I also figured out 950-962 are the Beaufort scale and adjusted accordingly http://www.spc.noaa.gov/faq/tornado/beaufort.html
Update WeatherToTextConverter.java
Merge pull request #1 from mfishma/master

Fix grammar for Codes Meanings