Fix debug build

Strong typedef is strong.
Move C++11 feature macros to PlatformConfig.h
CMakeLists.txt: Fix typo
Change default for DEBUG when build type changes

This makes is so that DEBUG is always enabled in CMAKE_BUILD_TYPE=Debug
builds unless the user has specifically disabled it with -DDEBUG=0
Add array-based platform::runHelper() variant
Add a yes/no dialog with "warning" decorations
CriticalErrorDialog: Support asking a question
Reduce the dialog spam on missing data files

It now asks the user before starting the data file installer.

This change makes the initial error dialog less scary by moving
technical information into the log file - it may be the first thing
many new users see.
arx-install-data: Probe Steam libraries for files
arx-install-data: Add support for more demo pkgs

- arx_demo_english.exe (same as regular demo, packages as RAR)
- arx_fatalis_demo_fr.zip
- arx_demo_german.exe
COPYING: Fix typo
arx-install-data: Update list of --disable-* args
arx-install-data: Don't always suggest --gui

If we launched ourselves in a terminal emulator because no GUI was
available, there is no point in suggesting the GUI mode as we already
know it won't (really) work.
Use $HOME over ~ for data dir config
Add a GL debug output option for release builds
When a bow is equipped, hero screen shows the base damage from arrows.