[BitBucket user: asch99]
[BitBucket date: 2017-09-13.09:20:36]

Static compilation of Orthanc 1.3.0 fails,  at least on Ubuntu 17.04 (and Fedora 25 as reported by somebody else on http://forum.dcmtk.org/viewtopic.php?f=3&t=4584).

Steps to reproduce:

```
#!python

  cmake -DSTATIC_BUILD=ON -DCMAKE_BUILD_TYPE=Release

```

It appears that the new DCMTK flag WITH_THREADS does not make it to the CMake files.
 
A simple fix (tested by me) would be the add the line

```
#!python

    SET(DCMTK_WITH_THREADS ON)

```

after the line 

```
#!python

    add_definitions(-DDCMTK_INSIDE_LOG4CPLUS=1)


```
at the beginning of
Resources/CMake/DcmtkConfiguration.cmake