added timeout support for Pimcore_Tool_Console::exec()

git-svn-id: http://www.pimcore.org/svn/pimcore/private/core/trunk@3860 1f8fe7d8-47f0-464c-8d0a-336f4953ab05
implemented Pimcore_Tool_Console::exec() timeout in HtmlToImage and Libreoffice adapters

git-svn-id: http://www.pimcore.org/svn/pimcore/private/core/trunk@3861 1f8fe7d8-47f0-464c-8d0a-336f4953ab05
build auto version (2951) ...

git-svn-id: http://www.pimcore.org/svn/pimcore/private/core/trunk@3862 1f8fe7d8-47f0-464c-8d0a-336f4953ab05