prevent disclosing full path when raising "Shaarli directory not writeable" error
 * work on https://github.com/shaarli/Shaarli/issues/78
prevent disclosing PHP version on PHP version check error
 * fixes https://github.com/shaarli/Shaarli/issues/78
 * fixes https://github.com/sebsauvage/Shaarli/issues/214
Merge pull request #81 from nodiscc/prevent-disclosure

Prevent full path and PHP version disclosures