Text Scaling is Inconsistent under GTK
Description
When the system text size is set in GTK, some elements in the GUI reflect this sizing and some do not.
Elements that have fixed text sizing:
There are quite a few others as well.
Steps to reproduce
- Set the GTK text size to 14 pt
- Launch KiCad
KiCad Version
Application: LibEdit
Version: (5.99.0-591-g2999bcb72), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.0 OpenSSL/1.1.1d zlib/1.2.11 libidn2/2.0.5 libpsl/0.20.2 (+libidn2/2.0.5) libssh2/1.8.0 nghttp2/1.36.0 librtmp/2.3
Platform: Linux 4.19.0-6-amd64 x86_64, 64 bit, Little endian, wxGTK
Build Info:
    Build date: Dec 29 2019 10:56:27
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
    Boost: 1.67.0
    OpenCASCADE Technology: 7.3.0
    Curl: 7.64.0
    Compiler: Clang 9.0.1 with C++ ABI 1002
Build settings:
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=ON
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=OFF
    KICAD_USE_OCC=ON
    KICAD_SPICE=ON
    KICAD_STDLIB_DEBUG=ON
    KICAD_SANITIZE=OFF



