Add onelogin.saml2.organization.lang attribute

[cgroix]

I put the attribute into the Organization, class, and overloaded the constructors, leaving the existing ones with a "en" default value.

This PR allows us to change this attribute without breaking existing configurations (including programmatic ones), even though it won't fully answer issue #102

[coveralls]

Coverage increased (+0.05%) to 95.117% when pulling ccf06b0 on cgroix:master into 5cd3ed8 on onelogin:master.

[coveralls]

Coverage decreased (-0.02%) to 95.043% when pulling 12c3a8e on cgroix:master into 5cd3ed8 on onelogin:master.

[pitbulk]

That PR includes not only the lang stuff, but a change on SamlResponse.java

I'm still thinking about how I gonna support multiple x509certs on Java as I already implemented it on the rest of toolkits, so can't merge that part.

Can you isolate the PR, adding only the "lang" part?

[cgroix]

Sorry, the PR was meant to include only the first three commits, I should have put the multiple cert part in another branch. I will clean that later today.

About the multiple Idp Cert, would you be interested in a PR changing the Saml2Settings class and the validation part ? I don't really care about the actual settings files and builder, since we use our own settings and extend Saml2Settings, but I can still implement that part, plus the fingerprint and log out .

[coveralls]

Coverage increased (+0.05%) to 95.117% when pulling 95549b5 on cgroix:master into 5cd3ed8 on onelogin:master.

[cgroix]

I cleaned the master branch