Merge pull request #30 from moteus/master

Add. test to set/unset postfields
Merge pull request #32 from moteus/master

Change. Returns nothing form reader callback means EOF.
Merge pull request #33 from moteus/master

Add. Ability to add easy handle during iteration.(close #25)
Merge pull request #34 from moteus/master

Add. pop3 example [ci skip]
Merge pull request #35 from moteus/master

Add. Use LuaCov
Merge pull request #36 from moteus/master

Update pop3 example [ci skip]
Merge pull request #37 from moteus/master

Fix. `MAIL_RCPT` option has a list type
Merge pull request #38 from moteus/master

Change. `multi:iperform` unset callback functions for easy handles.
Merge pull request #39 from moteus/master

Add. Supports `content` field in form:add().
Merge pull request #41 from moteus/master

Fix. rockspec install examples and docs.
Update README.md

[ci skip]