Assume that people use bundler

It's ubiquitous now.
Improve save_page for binary content
Issue #1229 - reset touched after session is reset
Allow expectations on element count in Finders#all().

- all() will now wait for the number of elements returned to match
  the expected :count, :minimum, :maximum, :between query options.
- Helpers#matches_count? returns true if none of the count  query
  options are specified.
- Helpers#matches_count? tests multiple conditions if more than one
  is specified. If :count is specified, however, it ignores others.
- Matchers#assert_selector allows checking for 0 matches when
  the query options include {:count => 0}
Fix spec failures
Add specs for new query options on Finders#all method
Un-DRY specs
Add .ruby-version and .ruby-gemset to .gitignore
Merge pull request #1230 from lesliepc16/reset_touched

Issue #1229 - reset touched after session is reset
add refute_selector as alias of assert_no_selector
Merge pull request #1234 from gregmolnar/refute

add refute_selector as alias of assert_no_selector
Merge pull request #1233 from abotalov/add_ruby_version_to_gitignore

Add .ruby-version and .ruby-gemset to .gitignore
Use let instead of tap
Remove options hash
Merge pull request #1222 from joliss/readme

Assume that people use bundler
Merge pull request #1223 from cschramm/patch-1

Improve save_page for binary content
Use options hash from query object
Run Travis tests on latest Chromedriver
Build on latest rbx version
Merge pull request #1240 from abotalov/use_rbx_on_travis

Use latest Chromedriver and rbx for Travis tests