Update buildignore and .gitignore files
Update get_wasp_trips to return more columns

Also allow the user to specify the time difference.
Update build-wasp-data.r to work with new function
Whoops, I had the time corrections backwards
Add to "returns" section of documentation
Swap away/home for arriving/leaving and flip default codes
Switch argument names and reverse group 2 codes
Merge pull request #3 from seananderson/return-more-data

Return more data