Python-weed

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supports python3.7+

- add prefetch volumeids for master to get volumeId more quickly;
- add WeedOperation.exists(fid) to detect fid's existence

add examples to README
bump version to v_0.1.6

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changelog:
- change default volume port 8080 to 27000
- change api module operation:
rename:
- create -> crud_create
- read -> crud_read
- update -> crud_update
- delete -> crud_delete
add:
- get_url -> return an accessible volume url of a "fid"
- get_content -> return just file content of a file
return value changed:
- now get/put/delete all return the same structure: WeedOperationResponse(wor)
- check operation's status by checking: wor.status (if ok: 'success' else 'fail' or 'error')

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changelog:
Modify "method: get" of WeedOperation. Change default Parameter
"just_url" to False and add Parameter "just_content"(defaults to
True).

So,
when you do "get" by default, you will get file content as normally expected;

set "just_url" to True you will get an object of WeedResponse
whose "property: fid_full_url" can serve as a full url for
backend servers like nginx, ...;

set "just_content" to True will just return the file's content
else will return a full object of requests.Response(includes all
info, like content-type, headers, ...)

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changelog:
add put/get/rm, create/read/update/delete operations