Normalize names

Created function for normalizing a vector of names in two steps:

I. Cleaning each string
   1. convert to all lower case
   2. convert accented characters (é) to their alphabetical counterparts (e)
   3. drop any remaining non-alphabetical characters ("-")
   4. replace empty names by 'anon'

II. Splitting it into first name, last name and any remaining characters

Example:

```
raw_names <- d$full_name[c(4,11,94,2470)] #where d is the output of merge_all_parties_and_years.R
raw_names #INPUT
normalize_names(raw_names) #OUTPUT
```

INPUT

| | 
 -------------
|Charles-Antoine Allain |
|Stéphane Allard |
|Charles E. Beaudoin|
||

OUTPUT

clean_full_name | last_name | first_name | remaining
------------- | ------------- | ------------- | -------------
charlesantoine allain    | allain | charlesantoine |
stephane allard |   allard   |    stephane |
 charles e beaudoin | beaudoin  |      charles | e
anon anon  |          anon | anon |

Note that the packages ``` dplyr``` and ``` magrittr```  are required.