Joker-cast

* improved Timer

* drop python 2.x support
* drop dependencies on six
* add syntax.Glass, syntax.Object
* remove syntax.format_class_path(), syntax.format_function_path() -- moved to volkanic.introspect
* long_description in setup.py
* remove j.c.circular, j.c.dictionary
* remove namedtuple_to_dict()

* add chunkwize_split()
* add iterative.until_convergent
* add split and generic_split
* add cumsum
* add chunkwize_split
* merge circular and dictionary into collective

* flatten `jc.iterative`: `jc.iterative`, `jc.circular`, `jc.dictionary`
* remove `jc.nested`

* add `jc.timedate.timed()`
* remove module `jc.locational`
* remove `jc.numeric.{floor,ceil}()`
* remove `jc.iterative.nonblank_lines_of()`

* rename `_first_arg` to `default_func` in `j.c.syntax`
* remove module `j.c.serialize`, `j.c.indented_json_print()`
* remove compat name `j.c.fmt_class_path` (use `j.c.format_class_path`)
* add `j.c.numeric.numsys_cast()`, `j.c.numeric.numsys_revcast()`
* remove compat name `j.c.fmt_function_path` (use `j.c.format_function_path`)
* move `j.c.multilevel_get()` to `j.c.nested.recursive_get()`
* remove `j.c.syntax.AttrEchoer`
* deprecate `j.c.locational` (moved to `joker` pakcage)
* add `j.c.cache_lookup()`
* add `j.c.timedate.time_format`, `j.c.timedate.smart_time_parse{,to_seconds,to_timedelta}`
* add `j.c.n.numsys_{cast,revcast}`
* add `j.c.timedate.sexagesimal_{format,parse}`
* add `j.c..Traverser.__call__`