gnucash maint: Bump minimum cmake version to 3.5

[Geert Janssens]

Updated	 via  https://github.com/Gnucash/gnucash/commit/b7479e8f (commit)
	from  https://github.com/Gnucash/gnucash/commit/ae76a294 (commit)



commit b7479e8fb0091ba4f6f4cc9af60a3b4ecb39d37b
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Sat May 25 11:20:21 2019 +0200

    Bump minimum cmake version to 3.5
    
    This version is available for all supported platforms and distros
    (CentOS can have a version via EPEL, which is required anyway)
    
    Advantages:
    - one cmake version for all platforms
    - we can drop all conditions based on cmake version



Summary of changes:
 CMakeLists.txt                                  |  57 +++---
 common/cmake_modules/CMakeLists.txt             |   2 +-
 common/cmake_modules/GncAddGSchemaTargets.cmake |   6 +-
 common/cmake_modules/GncAddSchemeTargets.cmake  |   6 +-
 common/cmake_modules/GncAddTest.cmake           |  14 +-
 common/cmake_modules/GncFindPkgConfig.cmake     | 256 ------------------------
 common/cmake_modules/MakeDist.cmake             |   9 +-
 common/cmake_modules/MakeDistCheck.cmake        |  13 +-
 gnucash/gnome/CMakeLists.txt                    |  10 +-
 gnucash/gschemas/CMakeLists.txt                 |   6 +-
 libgnucash/backend/xml/test/CMakeLists.txt      |   7 +-
 libgnucash/doc/design/CMakeLists.txt            |  19 +-
 libgnucash/quotes/CMakeLists.txt                |   8 +-
 po/CMakeLists.txt                               |   7 +-
 14 files changed, 47 insertions(+), 373 deletions(-)
 delete mode 100644 common/cmake_modules/GncFindPkgConfig.cmake