New Features - Prefixing, Suffixing, Number Commas and Ordinal

I've created a few new features, if you would prefer me to rip these out and submit them as individual PR's, let me know.

# Prefixes and Suffixes
Pretty simple, by using `data-prefix` and `data-suffix` you can prepend and append whatever you like to your numbers. Both the prefix and suffix will appear from the start and won't change throughout the countTo process.
```
<span class="timer" data-from="0" data-to="100" 
      data-prefix="Example: " data-suffix=" points"></span>

<script type="text/javascript"><!--
    $('.timer').countTo();
//--></script>
```
**Example: 100 points**

# Number Commas
By setting `data-commas` to anything (e.g. `data-with-commas="true"`), the current value during the countTo process will have commas placed in the correct locations. 

For example if you have `data-from="0"` and `data-to="1500"`, no commas will appear until the value has reached 1,000, at which point it (and all subsequent values) will be formatted with a comma.
```
<span class="timer" data-from="0" data-to="1500"
      data-with-commas="true"></span>

<script type="text/javascript"><!--
    $('.timer').countTo();
//--></script>
```
**1,500**

# Ordinal
By setting `data-ordinal` to anything (e.g. `data-ordinal="true"`), the value will be appended with the correct ordinal of the final `settings.to` value.

For example, if you have `data-from="10"` and `data-to="31"`, whilst the value is incrementing it will be appended with `st` as this is the correct ordinal for 21. I have tried setting this to dynamically update the ordinal as it increments/decrements, but doing it that way would lead to a weird bug where the ordinal would not change, and instead the ordinal would default to the ordinal of the `data-from` value.
```
<span class="timer" data-from="0" data-to="83"
      data-ordinal="true"></span>

<script type="text/javascript"><!--
    $('.timer').countTo();
//--></script>
```
**83rd**

# Correct Combinations
You can combine the usage of all 4 of these new tags and they'll play nicely together and with your current tags. `data-prefix` will always appear before the number, `data-append` will always appear after both the number and the ordinal.

```
<span class="timer" data-from="0" data-to="100" 
      data-prefix="Final Position: " data-suffix=" place" data-ordinals="true"></span>

<script type="text/javascript"><!--
    $('.timer').countTo();
//--></script>
```
**Final Position: 3rd place**
Hmm, I think it'd be nice to figure this out so we show the ordinal matching the currently displayed number rather than the last number that will be displayed.  One thing I just thought of too, what if decimals are displayed?  It would be weird to see something like "102.34nd" or "102.34th" (depending on the ordinal being based upon the "2" or the "4").