DS-148: CSS classnames refactoring
Jira: https://jira.it.helsinki.fi/browse/DS-148
Modified the class names of the following components so that they always have the ‘ds-’ prefix; also standardized class naming
- ds-text-input
- ds-button
- ds-input
Jira: https://jira.it.helsinki.fi/browse/DS-148
Modified the class names of the following components so that they always have the ‘ds-’ prefix; also standardized class naming