Merge pull request #168 from loleg/master

[#160][m]: Project page filtering from @loleg.
Initially filter to show only featured projects

Refs #160
[projects][xs]: rename timeliner to timemapper.
Make a subset of projects featured

Refs #161
Make frictionless data a featured project

Refs #161
Added OLAP posts: intro and logical model + images
Typos
Merge pull request #171 from Stiivi/master

[blog/new][l]: OLAP intro + model from @Stiivi.
Add tagline attribute to projects

Refs #161
Tidy up projects page js a little

Refs #162
Fix bug in 093b67c1 - repeated content in modals
Newsletter, 16 January
Merge pull request #172 from nmashton/master

Newsletter, 16 January
Fix bug in 093b67c1 - use data-filter
One more 093b67c1 bug.. concat filter string
[events][s]: add agenda calendar to sidebar of front page and join page.
[#73,events][s]: embed new google calendar on events page.
Merge branch 'master' of github.com:okfn/okfn.github.com
[hangouts][s]: update with latest hangout info.
Project filtering using chosen