Fix quotes

[akapust1n]

When trying to use a library, an error with incorrect quotes flies.

[mverbert]

3 points:

• sorry for the delayed response, but I lost my Internet connection at home in the recent days.
• my repo is a fork from https://bitbucket.org/tildeslash/libzdb.git (the original author) so your changes should be sent upstream instead.
• I don't understand how this commit fixes anything. Did you forget to install the headers (or to set the include path properly) ?