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

Use sqlite_ext 1.5.0 which has been broadened to work with Ruby
versions prior to 2.x, and remember to add it to files in the
./gemfiles/ directory for use with CI tests, not just to
Gemfile in the root directory.

Required for ruby 1.8.7 and 1.9.2 builds on travis.