Fix Locale & KeyPairGeneratorSpec deprecation warnings

[0biWanKenobi]

This commit resolves a few deprecation warnings by implementing dedicated methods:

• config.locale=locale has new method setSystemLocaleLegacy , otherwise config.setLocale(locale)
• context is set by new method setContextConfigurationLegacy ,otherwise context = context.createConfigurationContext(config);
• AlgorithmParameterSpec is obtained with new method makeAlgorithmParameterSpecLegacy, otherwise same as before

[mogol]

Thanks @0biWanKenobi