ValidationMessages: merge *name.hyphen

[php-coder]

category-name.hyphen = Country name must not start or end with hyphen
country-name.hyphen = Country name must not start or end with hyphen
name.hyphen = Name must not start or end with hyphen

We could use one message (like Value must not start or end with hyphen) for all of them.

[php-coder]

In this ticket you should do the following:

• add value.hyphen key with message Value must not start or end with hyphen to ValidationMessages.properties
• add value.hyphen key with message Значение не должно начинаться или заканчиваться знаком дефиса to ValidationMessages_ru.properties files
• remove category-name.hyphen, country-name.hyphen and name.hyphen from these files
• replace all occurences of category-name.hyphen, country-name.hyphen and name.hyphen inside project by key value.hyphen