Fixed ZendServer specific DLL Path in install doc

It seems the \ need to be escaped in the tip section.

(see the file on github or the Twig website)
minor #1259 Fixed ZendServer specific DLL Path in install doc (tucksaun)

This PR was merged into the master branch.

Discussion
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Fixed ZendServer specific DLL Path in install doc

It seems the \ need to be escaped in the tip section.

(see the file on github or the Twig website)

Commits
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2b102e3 Fixed ZendServer specific DLL Path in install doc