ENH: Python parser now accepts delim_whitespace=True
Title is self-explanatory.

can you confirm with #12686 that all options are covered?
 I think doc-string and io.rst need small edits for this (to remove that this is only for c engine)
 I don't quite understand your question.  Could you clarify?

Ah, yes, good point.  Need to change what I just added since it's supported for Python now!
 I meant we are now listing all of the options in that issue so that we can check them off. And you have them listed in the variables to check for the options, just want a cross check.

bonus points if you can autogenerate a section in the doc-string which explicity lists the unsupported options (by using those variables). Or maybe don't need to auto-generate, maybe just list a section in doc-string & io.rst to at least list the un-described / only certain engine supported options.
 Well, they used to be a copy of `_c_parser_defaults`, which I would consider to be the "correct" version until demonstrated otherwise (Python will raise if any of these are passed with a `python` engine specified).  So in fact the list for C-only features in #12686 should be the one I created in this PR, which it is not.
 @gfyoung if you can post a correct list I will update
 FYI, Travis has just given the green light for my changes, so if you don't have any other code-related complaints, I'll update the documentation with `[ci skip]`.
 <pre>
as_recarray
na_filter
compact_ints
use_unsigned
low_memory
memory_map
buffer_lines
error_bad_lines
warn_bad_lines
dtype
decimal
float_precision
</pre>

If any of these are non-default with a `python` engine, the parser will raise.
 ok I edited the other issue, pls have a look
 Are those uncapitalised headers (e.g. "undocumented in C engine only") sub sections for "Features supported in the C engine only"?  If not, all of the ones that I listed just now should also go under "Features supported in the C engine only"
 ty
