Support negative patterns in host lookup from the SSH config file.

Fixes #150: ssh_config parsing doesn't support negated host patterns
Merge pull request #163 from nirvdrum/negative_host_patterns

Support negative patterns in host lookup from the SSH config file.
Update .travis.yml

Temporarily removed Ruby 2.1.0 to resolve Travis issue (travis-ci/travis-ci#2220).
Add manual test for Pageant negotiation.
Add external methods for security attribute acquiration.
Progress on 1.9.3 implementation.
Working with elevated console and elevated or limited Pageant.
Add 1.8.7 implementation.
Clean up. Partial fix for #92. Does not work with KeeAgent.
Cleaner compatibility. Fixes #92.
Consolidate send_query methods and add unicode checking.
Remove unnecessary unicode code, fix length determination and implement KeeAgent support.
Add better documentation to Pageant test.
Clearer C string handling.
Merge branch 'master' of github.com:net-ssh/net-ssh
Merge pull request #165 from chrahunt/add-security-attributes-pageant

Add user security attributes for Pageant
Merge branch 'master' of github.com:net-ssh/net-ssh
Version bump (2.9.1)
Adapt comment
Fix regular expression for Ed25519 case