added Clock class which provides a monotonic clock on most platforms and is now used by Poco::Timer, Poco::Stopwatch, Poco::TimedNotificationQueue and Poco::UtilTimer to avoid issues when the system time is changed
Poco::Util::Timer now uses Poco::Clock instead of Poco::Timestamp
Clock fixes
add error code to TimeoutException, where available
improved error handling, specifically socket timeouts
fixed license headers
.travis.yml: install unixodbc-dev libmysqlclient-dev

Signed-off-by: Roger Meier <roger@bufferoverflow.ch>
Merge pull request #349 from bufferoverflow/travis

.travis.yml: install unixodbc-dev libmysqlclient-dev
fixed GH# 350: Memory leak in Data/ODBC with BLOB
Merge branch 'develop' of https://github.com/pocoproject/poco into develop
updated CHANGELOG
Removed redundant #includes and fixed spelling mistakes.
Merge pull request #352 from latitude37s/develop

Removed redundant #includes and fixed spelling mistakes.
Correctly set MySQL time_type for Poco::Data::Date.
fieldSize() returns std::size_t, which is not necessarily the same width as unsigned long.
Merge pull request #353 from latitude37s/develop

Correctly set MySQL time_type for Poco::Data::Date.
Fixed setting of MYSQL_BIND is_unsigned value.
.travis.yml: use -y option for apt-get upgrade and install
Merge pull request #356 from bufferoverflow/travis

.travis.yml: use -y option for apt-get upgrade and install
Merge pull request #355 from latitude37s/develop

Fixed setting of MYSQL_BIND is_unsigned value.