import: changed default port: 80 to 443
Fix missing definition of APIError
Allow 'td -k' without config file
Configure SSL correctly for bulk import library
Always validate the endpoint parameter
Handle missing config file for endpoint retrieval
Handle accessing trouble to maven.treasure-data.com

Changes:
- Handle SocketError, Net::HTTPBadResponse, Errno::ECONNREFUSED
  suppressing the stack trace and returning the error message
- Avoid progressing in the update of the jar file if any
  connection trouble occurred

Fix for CLT-280
Only show result if the job is finished
Update td-client gem dependency to 0.8.61
Upgrade from ruby 1.9.3-p194 to p545 - the former no longer available
Use proxy for jar file and toolbelt update

Changes:
- wrap the HTTP class in a function from common.rb:
  'get_http_class'
- if HTTP_PROXY is defined in the environment variables,
  instantiate Net::HTTP::Proxy instead of simply Net::HTTP
- use the result of 'get_http_class' in both the 'fetch'
  and 'stream_fetch' functions
- create a DownloadProgressIndicator class and a derived
  TimeBasedDownloadProgressIndicator in common.rb
- simplify the progress indicator handling in both
  self.update and jar_update methods by using the
  TimeBasedDownloadProgressIndicator methods
- make both humanize_time and humanize_elapsed_time
  static methods

Implements CLT-314.
Fix broken variable name from commit d18296b2

Add a fix for CLT-314
import: refactored HTTP proxy settings

Fixed CLT-313.
Fix usage of humanize_* methods, made static in commit d18296b2
Disable JAR autoupdate on request

Changes:
* If TD_TOOLBELT_JAR_UPDATE environment variable is set to
  0, skip JAR autoupdate but still allow manual update
  via 'import:jar_update'
* add testing hooks list to README

Implements CLT-319