Allow passing JSON queries straight to Druid in post_query

Allow passing JSON queries straight to Druid in post_query (#63)

This makes it possible to use any kind of query, regardless of whether
Panoramix has support for building and encoding it.

Allow capitalized aggregation types

Some HLL aggregation names are capitalized and therefore won't play well with from macro. For such cases
use their aliases as a workaround: hllSketchBuild, hllSketchMerge, hllSketchEstimate, hllSketchUnion, hllSketchToString.

Allow lookups in filters

Allow lookups to be used on dimensions in filters (#53)

The syntax is:

    dimensions.foo |> lookup(:lookup_name)

Add status code field to exception

Merge pull request #39 from GameAnalytics/add-status-code-to-error

Add status code to exception thrown

Persist context defaults

If user supplied context parameters of timeout or priority are missing then populate them with defaults from app config.
Additional work done on .travis.yml to publish the package to hex.

Rewrite "not" filter generation

Merge pull request #33 from GameAnalytics/rewrite-not

Rewrite "not" filter generation

Merge "and" filters

Merge pull request #32 from GameAnalytics/merge-and

Merge "and" filters

Rename to Panoramix

0.10.0

Travis.com -> Travis.org

Add fields needed for search query

Merge pull request #27 from GameAnalytics/search-query-fields

Add fields needed for search query

Change post_query argument order

Merge pull request #26 from GameAnalytics/arguments

Change argument order, add default value