cmake: error no LIBRARY DESTINATION for shared library target.

[ArthurSonzogni]

When doing

cmake ..

I get:

CMake Error at CMakeLists.txt:79 (INSTALL):
  INSTALL TARGETS given no LIBRARY DESTINATION for shared library target
  "libglew_shared".


CMake Error at CMakeLists.txt:94 (INSTALL):
  INSTALL TARGETS given no LIBRARY DESTINATION for shared library target
  "libglewmx_shared".


-- Configuring incomplete, errors occurred!

I bisected. This is caused by the merge:

---

commit e4de8a7
Merge: f92c14b 5a7232f
Author: Gyusun Yeom omniavinco@gmail.com
Date: Sat Apr 20 15:45:09 2019 +0900

Merge pull request #16 from GekkieHenkie/patch-1

Update library install directories in Cmake

---

commit 5a7232f
Author: GekkieHenkie 33967804+GekkieHenkie@users.noreply.github.com
Date: Tue Apr 9 23:59:48 2019 +0200

Install directories set in single statement

---

commit def19e7
Author: GekkieHenkie 33967804+GekkieHenkie@users.noreply.github.com
Date: Tue Apr 9 23:22:16 2019 +0200

Update library install directories in Cmake

Currently (well, at least on Windows), the created DLL files aren't installed to the correct directory after a build. The DLL files are installed to the 'lib' directory. Which actually is the place for the static library or the shared library's symbols file (.lib).
The shared library runtimes should be installed to the 'bin' output directory, as proposed in this PR.

See the ```CONFIGURATIONS``` option in [Install command introduction in the CMake manual](https://cmake.org/cmake/help/v3.14/command/install.html#introduction) for an example.

It's considered best practice and follows convention as used in other notable libraries as libpng, libogg/vorbis, freetype, zlib, tinyxml, etc, to install the runtime output in the 'bin' directory.

[ArthurSonzogni]

Fixed.