Grammar mistake 

Line 176:
Using the `files` object, you can have list any number of source-destination pairs. 
Changed to:
Using the `files` object, you can list any number of source-destination pairs.
Merge pull request #107 from moxizhou/master

Fix Grammar mistake
Tokenize dummy source map on words and new lines.

@Toilal, in #96, brought up a good point that improves line numbers
mapping. This takes that into consideration by improving the regex to
create newlines as separate tokens. It also makes tokens from white
space, letting non word characters be tokenized if they are surrounded
by whitespace.