Merge branch 'fix_boost' into 'master'

disable file_converter if boost is not found.

See merge request !17
12 jobs for master in 3 minutes and 43 seconds
Status Job ID Name Coverage
  Test
passed #21651
VS2013
VS2013-32-bit

00:00:50

passed #21650
VS2013
VS2013-64-bit

00:00:52

passed #21649
VS2015
VS2015-32-bit

00:00:58

passed #21648
VS2015
VS2015-64-bit

00:01:08

passed #21642
Linux
clang-c++11

00:02:23

passed #21644
Linux
clang-c++98

00:01:52

passed #21647
Linux
cppcheck

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passed #21652
Linux
doc

00:00:18

passed #21641
Linux
gcc-c++11

00:03:43

passed #21643
Linux
gcc-c++98

00:02:45

passed #21645
Apple
macos-c++11

00:01:23

passed #21646
Apple
macos-c++98

00:01:20