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Remove InstallDev section. This is already included with CMAKE_INSTALL.

Minor cleanups.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

The latter is actually what is used by the build system. Increased
PKG_RELEASE for all packages as this changes the ipk.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

log4cplus is a simple to use C++11 logging API providing thread--safe,
flexible, and arbitrarily granular control over log management and
configuration. It is modeled after the Java log4j API.

wiki: https://sourceforge.net/p/log4cplus/wiki/Home/
github: https://github.com/log4cplus/log4cplus

Signed-off-by: BangLang Huang <banglang.huang@foxmail.com>