Add source code and changelog links to gemspec

add support for abbrv param

OpenCage recently added a new optional parameter "abbrv".
Some details: http://blog.opencagedata.com/post/160294347883/shrtr-pls

Add `:params` for geocoded_by and reverse_geocoded_by

add connreset to network errors

Change documentation about pelias

It seems that pelias section had the same links as mapzen. Changed that so that it points to pelias github page.

Allow to limit the objects that will be geocoded by rake task

add ip_lookup option to initializer template

I noticed this option was in the README, but not in the template, so it
might be nice to have it generated in the template as well.

return state_code instead of alias state

Current webmock is not compatible w/ Ruby <2.0.

* Added support for AMap, aka AutoNavi Map, 高德地图

* Try to include amap error info if failed

* Get correct result from amap response

* Fix result error in amap return

* Refactor codes for AMap handling

* Refactor codes for amap result handling

* Refactor amap handling codes

* Fixed coordinates handling error

* Added tests

* Fixded amap result handling and tests

* Lock webmock on 2.3.2 for ruby 1.9.3 support

Maxmind geoip2 returns a collection of names in all available languages
for each field.
This commit allows us to change the language of a single result without
having to reconfigure Geocoder.

* Create methods removing port from ip addresses; Add test

* Update geocoder_reject_non_ipv4_addresses; Add more tests

fix comment describing the required cache interface

Update smarty streets search results coordinates method to return nil 

Update smarty streets results coordinates method to return nil when both latitude and longitude do not exist

cache must respond to #del, not #keys

Add street and street_number methods to Yandex lookup