Initial import for libcouchbase 2.4
Update libcouchbase 2.4 docs
Add .swp to gitignore
Add release notes for lcb 2.4.0-dp1
Add release notes for 2.4.0-beta
Merge pull request #141 from mnunberg/stage

Libcouchbase 2.4-beta Docs
C SDK: add version 2.4 beta
update links to C v2.4 API reference