(#583) - compact callback after compaction's done

Now http adapter behaves like others. The code manually pings
database to check if it's done compaction.
(#583) - uncomment compaction test

This test was failing due to http compaction took some time
and callback was fired before it finished. Now it's fixed
(#583) - add compaction documentation
Merge pull request #593 from neojski/583-call-compact-callback-when-done

583 call compact callback when done
Revert "Merge pull request #593 from neojski/583-call-compact-callback-when-done"

This reverts commit 62887f91b824af30e2614b29c298750e88e834c2, reversing
changes made to 9113aca3feefa843cbc91626b5d81f4f14d32e3d.
Add test for plain replicate api
Change the order of parameters in replicate
Remove unwanted console.log
Added Tests cases for correct allDbs return format

The correct format for allDbs is:
- adapter prefix to be included if pouch was created with adapter prefix
  specified.
Updated allDbs to return correct format for Pouch names
Updated addDbs API documentation
Registered 'browser' task for browser tests
Updated CONTRIBUTING.md to reflect new grunt task
Merge pull request #601 from daleharvey/gruntfile-improvements

Gruntfile improvements
Merge pull request #602 from daleharvey/570-allDbs-protocol-prefix

#570 allDbs protocol prefix
(#603) - fix + test
(#606) - Ensure tests start() is called after completion
Merge pull request #605 from neojski/603-open_revs-with-revs

(#603) - fix + test
Merge pull request #607 from daleharvey/fix-gql-tests

(#606) - Ensure tests start() is called after completion
Merge pull request #595 from chunmun/572-broken-replicate

572 broken replicate