Merge branch 'release/0.6.2' into develop
fix #15 (invalid soql building from $exists operator)
fix soql building error when operand value is empty array
add soql-builder test for $exists operator
Merge branch 'fix/id/15' into develop
change ver to 0.6.3
update change history in README.md
Merge branch 'release/0.6.3'
Merge branch 'release/0.6.3' into develop
Update README.md

updated typo
Merge pull request #19 from givingstage/master

Update README.md
Added unsubscribe capability to streaming topics
change ver to 0.6.4
Merge branch 'release/0.6.4'
Merge branch 'master' into gh-pages
regenerate jsdoc