Remove warnings

[tagomoris]

This change is to suppress Ruby runtime warnings. Those are harmful because we may miss really important warnings because of noisy & less-serious warnings.

I saw those from fluent-plugin-td test runnings.

lib/td/client/api.rb:566: warning: `&' interpreted as argument prefix
lib/td/client/api.rb:673: warning: character class has duplicated range: /[^\-_!~*'()~0-9A-Z_a-z]/
lib/td/client/api.rb:683: warning: character class has duplicated range: /[^\-_!~*'()~0-9A-Z_a-z]/
lib/td/client/api/bulk_import.rb:15: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:27: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:77: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:90: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:102: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:114: warning: assigned but unused variable - body
lib/td/client/api/bulk_import.rb:139: warning: assigned but unused variable - body
lib/td/client/api/database.rb:30: warning: assigned but unused variable - body
lib/td/client/api/database.rb:42: warning: assigned but unused variable - body
lib/td/client/api/job.rb:89: warning: assigned but unused variable - ignored_e
lib/td/client/api/result.rb:28: warning: assigned but unused variable - body
lib/td/client/api/result.rb:38: warning: assigned but unused variable - body
lib/td/client/api/schedule.rb:60: warning: assigned but unused variable - body
lib/td/client/api/server_status.rb:11: warning: assigned but unused variable - res
lib/td/client/api/table.rb:49: warning: assigned but unused variable - body
lib/td/client/api/table.rb:62: warning: assigned but unused variable - body
lib/td/client/api/table.rb:74: warning: assigned but unused variable - body
lib/td/client/api/table.rb:96: warning: assigned but unused variable - body
lib/td/client/api/table.rb:145: warning: assigned but unused variable - body
lib/td/client/api/user.rb:47: warning: assigned but unused variable - body
lib/td/client/api/user.rb:57: warning: assigned but unused variable - body
lib/td/client/api/user.rb:69: warning: assigned but unused variable - body
lib/td/client/api/user.rb:90: warning: assigned but unused variable - body
lib/td/client/api/user.rb:102: warning: assigned but unused variable - body
lib/td/client/api/user.rb:114: warning: assigned but unused variable - body
lib/td/client/api/user.rb:126: warning: assigned but unused variable - body
lib/td/client/model.rb:631: warning: assigned but unused variable - type
lib/td/client/model.rb:633: warning: assigned but unused variable - org_name

[coveralls]

Coverage decreased (-0.02%) to 79.774% when pulling 1b79b12 on remove-warnings into 2340ab9 on master.

[coveralls]

Coverage decreased (-0.02%) to 79.774% when pulling 1b79b12 on remove-warnings into 2340ab9 on master.

[coveralls]

Coverage decreased (-0.02%) to 79.774% when pulling 1b79b12 on remove-warnings into 2340ab9 on master.

[tagomoris]

Hmm, build failure on CI relates with SSL version (SSLv3). I guess it's caused by newer OpenSSL version, which just ignore SSLv3 as an invalid version... Is that correct?

[nurse]

Maybe the libssl is build with NO_SSLv3 option.

[nurse]

Anyway could you suppress the error with branching whether the openssl has SSLv3 or not.

Additional to say could you add Ruby 2.6.5 to .travis.yml?