Add join() with compatibility with SQL Join; improve .name handling; improve .from_csv(), .from_pdf(); fix concat bug; Add .attrs (similar to pandas).
This version provides some enhancements just prior to adding extensions for SQL proxy operation.
Added from_lot() class method. Perhaps these can be unified in main init function by examining type of the data passed.
Added join() method, including unit tests.
Added from_pdf() class method, used to parse PDF files with table structure across multiple pages.
Added name argument to from_lod()
Added name argument to from_csv_buff()
using raw docstring format to avoid complaints of escape characters in derive_join_translator.
Added 'tag_other' boolean parameter to tag all other column names during join, to support chained joins.
Simplified translator_daf table so it is easier to produce by hand and use across many tables being joined.
Added name argument for join() method, to provide the name of the resulting joined instance.
Improve unit tests for derive_join_translator
Added 25 tests for various indexing modes.
corrected parsing of tuple of strings for krows and kcols.
Added name argument for clone_empty() method.
Added omit_other_cols parameter for 'derive_join_translator' method.
this can probably displace the "shared_fields" parameter.
Fixed omit_other_cols so it could be properly omitted.
concat (which is called by append if a daf array is appended) was not using deep copy when
copying in the frame, and this became a real mess. Added copy with deep to concat.
Added from_csv() which will load csv to Daf from local files, s3 path or http/s path.
improved operation of streaming from file to avoid buffer recopying.
from_csv_buff() still exists for those times when a buffer or file-like object already exists.
Added .attrs dictionary to core dataframe instance definition to allow for descriptors to be
provided to users of the dataframe, esp. between when the daf array is defined and built
and when it is used and modified.
Improve file closure by using context manager in from_csv() for local file usage.
Deprecated use of utils instead of daf_utils.