Merge pull request #1 from notrix/master

Methods to encode user entity for registering or updating users
Added payment password functionality
Added client & their hosts, project & their locations management.
Paysera_WalletApi_Exception_ResponseException bug

Paysera_WalletApi_Exception_ResponseException method getStatusCode
returned full error message (e.g. "404 Not Found") instead of only
http status code (e.g. 404).
Negative amount fix
Added reduce payments prices feature when confirming transaction
Fix for negative amounts
Generating uri for user password change
Merge branch 'master' of https://github.com/paysera/lib-wallet-php-client