support passwordless connection with PostgreSQL database
Merge branch 'master' into 30-passwordless
User Mustache syntax for string interpolation

Deprecate previous syntax
Specify .GlobalEnv for call to whisker.render()
Added whisker is a suggested dependency
Fixed error in documentation
Removed deprecation for GetlongOpt string interp

There are still some edge cases with Mustache

Keeping GetlongOpt string interpolation in for the foreseeable future
until the edge cases with Mustache are worked out

Example edge cases:

Mustache still won't access slots: myObject@var

Mustache syntax does not handle function calls very well.
Will need to write specific examples
and explore more what kind of function calls are possible
and what are not.
Parse Mustache with strict = FALSE flag

Need to parse in non-strict mode to recognize '$' as the dereference operator
and include '.' in the variable name
support passwordless connection with PostgreSQL database
Added ElasticSearch Reader
Create add.extension(extenstion, reader) function

This allows the addition of custom readers.
Removed ElasticSearch reader from dependencies

Including the ES reader causes problems with travis CI

Plan is to allow additon of custom readers through packages
Load reader files in lib directory

Custom reader files can be added to the lib director
load.project will load these readers and apply them to data in the data folder
Removed elasticsearch reader

ElasitcSearch Reader is moved to https://github.com/KentonWhite/esReade

Install package and add esReader to libraries in global.dcf
Moved add.extension to .add.extension

Preface add.extension with a . to indicate that it should be treated as hidden

Exported .add.extension to indicate that this is a stable, public interface
Updated Changelog
Move tests/5.R to tests/6.R

Conflict with test file in develop branch
Added ElasticSearch Reader
Create add.extension(extenstion, reader) function

This allows the addition of custom readers.
Removed ElasticSearch reader from dependencies

Including the ES reader causes problems with travis CI

Plan is to allow additon of custom readers through packages