Changes in version 0.5.1 (2017-05-25)

 * Rename "text" class to "corpus_text" to avoid name classes with grid.

 * Rename "jsondata" to "corpus_json" for consistency.

 * Fix bug in read_ndjson() for reading factors with missing values.


Changes in version 0.5.0 (2017-05-23)

 * Add term_counts() function to tabulate term frequencies.

 * Add term_matrix() function to compute a term frequency matrix.

 * Add text_filter() option ("stem_except") to exempt specific terms from
   stemming.

 * Add text_filter() option ("drop") to drop specific terms, along with
   option ("drop_except") to exempt specific terms from dropping.

 * Add text_filter() option ("combine") to combine multi-word phrases like
   "new york city" into a single term.

 * Add text_filter() option ("select") to select specific terms (excluding
   all words that are not on this list).

 * Rename text_filter() options "fold_case", "fold_dash", "fold_quote"
   to "map_case", "map_dash", "map_quote".

 * Add stopwords() function.

 * Make read_ndjson() decode JSON strings as character or factor (according
   to whether "stringsAsFactors" is TRUE) except for fields named "text",
   which get decoded as text objects.


Changes in version 0.4.0 (2017-05-16)

 * Allow read_ndjson() to read from connections, not just files, by
   reading the file contents into memory first. Use this by default
   instead of memory mapping.

 * Rename text_filter() option "drop_empty" to "ignore_empty".

 * Add text_filter() options "drop_symbol", "drop_number", "drop_letter",
   "drop_kana", and "drop_ideo"; these options replace the matched tokens
   with NA.

 * Fix internal function namespace clashes on Linux and other similar
   platforms.


Changes in version 0.3.0 (2017-05-04)

 * Support for serializing dataset and text objects via readRDS() and
   other native routines.  Unfortunately, this support doesn't come for
   free, and the objects take a little bit more memory.

 * More convenient interface for accessing JSON arrays.

 * Rename as.text()/is.text() to as_text()/is_text(); make as_text()
   retain names, work on S3 objects.

 * Add support for stemming via the Snowball library.

 * Rename read_json() to read_ndjson() to not clash with jsonlite.

 * Rename "dataset" type to "jsondata".

 * Make read_ndjson() return a data frame by default, not a "jsondata"
   object.


Changes in version 0.2.0 (2017-04-15)

 * First CRAN release.

 * Added Windows support.

 * Added support for setting names on text objects.

 * Added documentation.


Changes in version 0.1.0 (2017-04-11)

 * First milestone, with support for JSON decoding, text segmentation,
   and text normalization.
