cmake: set minimum Boost version 1.53.0

boost::multiprecision was introduced in 1.53.0, which has been tested
successfully with PFASST++

this fixes #104
Merge pull request #119 from torbjoernk/feature/boost-version

cmake: set minimum Boost version 1.53.0
Merge branch 'development' into feature/build-tweaks

* development:
  cmake: set minimum Boost version 1.53.0

Signed-off-by: Torbjörn Klatt <t.klatt@fz-juelich.de>

Conflicts:
	3rdparty/CMakeLists.txt