Fix #93 again: ActiveSupport::SafeBuffer#gsub bug
simpler FakeSafeBuffer implementation for testing

references #93
Merge branch 'jgarber-master'

Fix ActiveSupport::SafeBuffer#gsub bug again

Fixes #93, closes #260
avoid ruby syntax warnings
use Minitest 5.0
fix randomly failing tests due to improper teardown
configure `script/test` to not tolerate Ruby warnings

This makes CI fail if code is added to the project that generates
warnings in Ruby's verbose mode.
proper loading of minitest

blessed by @zenspider:
https://twitter.com/the_zenspider/status/348563962880733184
fix brittle URI parser tests failing on Rubinius

The tests relied on the output of Method#to_s, which seems unreliable on
non-MRI Rubies. Avoid that and ensure the default_uri_parser is restored.
fix minitest require in Bundler standalone mode

https://travis-ci.org/lostisland/faraday/jobs/8411907

In Bundler standalone, the `gem` method is still available but the
minitest gem won't be found. Only use the `gem` method when we're
running in the context of Bundler normal mode.
remove void configure_ssl for EventMachine

It never seems to have served any purpose
avoid double loading of certain source files on Ruby 1.8.7

The "already initialized constant NET_HTTP_EXCEPTIONS" and related
warnings would pop up due a circular references triggered by
autoloading.

References #343
fix multipart post for servers that choke on Content-Type

Some servers such as Exchange 2010 don't like that there isn't a space
after a semicolon separator in the Content-Type request header. Since
Net::HTTPHeader#set_content_type adds the space, as well as it appearing
in the examples of RFC 2616, this follows suit and adds a space which
should help bad-behaving servers and not harm others.
add "http://" scheme to ENV['http_proxy'] value if missing

This allows:

    http_proxy=localhost:8888 ruby myscript.rb

Omitting the scheme is already supported by curl, and this matches that
behavior.
don't swallow exceptions in em-synchrony
ensure consistent handling of connection failures

All adapters should now raise Faraday::Error::ConnectionFailed
handle connection failure in HTTPClient adapter
add HTTP proxy authentication support to EM adapters
add HTTP proxy support for Excon
fix HTTP proxy authentication for Patron