REDCapR: REDCapR 0.9.6

New Features:

• Support for filtering logic in redcap_read() and redcap_read_oneshot() (PR #126)
• New functions retrieve_credential_mssql() and retrieve_credential_local(). These transition from storing & retrieving just the token (ie, retrieve_token_mssql()) to storing & retrieving more information. retrieve_credential_local() facilitates a standard way of storing tokens locally, which should make it easier to follow practices of keeping it off the repository.
• Using parameterized queries with the RODBCext package. (Thanks @nutterb in issues #115 & #116.)
• Remove line breaks from token (Thanks @haozhu233 in issues #103 & #104)

Minor Updates:

• When combining batches into a single data.frame, data.table::rbindlist() is used. This should prevent errors with the first batch's data type (for a column) isn't compatible with a later batch. For instance, this occurs when the first batch has only integers for record_id, but a subsequent batch has values like aa-test-aa. The variable for the combined dataset should be a character. (Issue #128 & http://stackoverflow.com/questions/39377370/bind-rows-of-different-data-types; Thanks @arunsrinivasan)
• Uses the dplyr package instead of plyr. This shouldn't affect callers, because immediately before returning the data, REDCapR::redcap_read() coerces the tibble::tibble (which was formerly called dplyr::tbl_df) back to a vanilla data.frame with as.data.frame().
• A few more instances of validating input parameters to read functions. (Issue #8).