Add support for exporting mongoDB contents into elasticsearch

Added essync tool to manually export data from mongoDB into
elasticsearch. This work was done with jrwren.
Updated with review comments
Merge pull request #124 from mhilton/exportv4-cs-mongodb-into-es

Exportv4 cs mongodb into es

Added support for uploading mongodoc.Entity objects into elasticsearch and provide a tool to migrate them from an existing mongoDB database.
Added elasticsearch configuration to charmstore.

The config.yaml file can now contain an optional
elasticsearch-addr parameter specifying an
elasticsearch endpoint to connect to for searching.
Merge pull request #127 from mhilton/es-config

Added elasticsearch configuration to charmstore.

The config.yaml file can now contain an optional
elasticsearch-addr parameter specifying an
elasticsearch endpoint to connect to for searching.
lppublish: fix limit
lppublish: fix build
Merge pull request #129 from rogpeppe/059-fix-counter

lppublish: fix limit

Since publishTips was introduced, the old limit counting was not
appropriate, as it would start again when ingesting bundles.

This fixes that.
lppublish, cmd/charmload: ingest exact revisions from legacy charm store
Merge pull request #128 from rogpeppe/058-use-legacy-revisions

lppublish, cmd/charmload: ingest exact revisions from legacy charm store

This behaviour is controlled by the new "-legacy" flag to charmload, which should
be used just once, when initially uploading charms.

In passing, also adjusted log messages somewhat so the logging at INFO
level is a little quieter and more informative.
remove test dir

move elasticsearch_test.go from test dir
Do not increase download counts on the old charm store while ingesting.
Merge pull request #131 from frankban/stats-zero

Do not increase download counts on the old charm store while ingesting.
don't spin up elasticsearch

Use a unique index name for all the tests.
move NewIndex calls to SetUp
Merge pull request #132 from jrwren/elasticsearch-no-spinup

don't spin up elasticsearch

Use a unique index name for all the tests.
fix comment
Merge pull request #133 from jrwren/elasticsearch-no-spinup

fix comment
When adding charms or bundles to mongo, index in ES if configured. Also, add EnsureID to ElasticSearch.
Merge pull request #134 from bac/update-es-on-doc-change

When adding charms or bundles to mongo, index in ES if configured.

Also add EnsureID to ElasticSearch.