Removed obsolete work from travis. Updated OSX image version.
Removed obsolete work from travis. Updated OSX image version.

VirgilSecurity/virgil-sdk-keys-ios,VirgilSecurity/virgil-sdk-keys-x,VirgilSecurity/virgil-sdk-keys-ios,VirgilSecurity/virgil-sdk-keys-x,VirgilSecurity/virgil-sdk-keys-ios,VirgilSecurity/virgil-sdk-keys-x,VirgilSecurity/virgil-sdk-keys-ios,VirgilSecurity/virgil-sdk-keys-x