Add support for @link{symbol|text}

Creates link to `symbol` with `text` as a text.

Signed-off-by: Jiří Janoušek <janousek.jiri@gmail.com>
Fix format of @param directives

Signed-off-by: Jiří Janoušek <janousek.jiri@gmail.com>
Rich formatting of list of params

Signed-off-by: Jiří Janoušek <janousek.jiri@gmail.com>
Add params to signal signature description

Signed-off-by: Jiří Janoušek <janousek.jiri@gmail.com>