initial commit of .4 branch.  .iso() factory method, ISO auto-parsing in parser
add 'iso' to module api
correct return type for iso factory method, some docs
remove old 0.1 arrow factory method support
walked back .iso() method, cleaned up .get() and implemented there
week support for range
span_range rewrite, week support
probably working week support for span_range, span
range tests rewritten
removed debugging print statements
span_range tests rewritten
Merge branch 'master' into 0.4
use ISO weekday standard of monday as day 1
week support for .replace
updated history
week test for span_range
int, float, string timestamp conversion moved factory -> arrow
print statement removed
history, docs update
README update