-Codechange: Remove _avail_aircraft
Its name is misleading. It is rather _avail_airports, but then only some of them, which leads to inconsistencies when using it.
Further it is unnecessary to store it in savegams.
- A proper ./configure, so everything needs to be configured only once, not for every make.
- Usage of makedepend when available. This greatly reduces the time needed for generating the dependencies.
- A generator for all project files. There is a single file with sources, which is used to generate Makefiles and the project files for MSVC.
- Proper support for OSX universal binaries.
- Object files for non-MSVC compiles are also placed in separate directories, making is faster to switch between debug and release compiles and it does not touch the directory with the source files.
- Functionality to make a bundle of all needed files for for example a nightly or distribution of a binary with all needed GRFs and language files.
Note: as this merge moves almost all files, it is recommended to make a backup of your working copy before updating your working copy.
