This safely saves a configuration file, optionally with a backup.

This allows config file values to defer to their defaults instead of
being null.

Prevents issues on specific locales, especially where decimal points are
represented by commas rather than periods.

This allows the 0x* format of hexadecimal integers to be used as config
integers.

This allows opening ini config data from a string.  Before, it was only
possible to load config from a file.

This Fixes a minor flaw with the API where data had to always be mutable
to be usable by the API.

Functions that do not modify the fundamental underlying data of a
structure should be marked as constant, both for safety and to signify
that the parameter is input only and will not be modified by the
function using it.

Typedef pointers are unsafe.  If you do:
typedef struct bla *bla_t;
then you cannot use it as a constant, such as: const bla_t, because
that constant will be to the pointer itself rather than to the
underlying data.  I admit this was a fundamental mistake that must
be corrected.

All typedefs that were pointer types will now have their pointers
removed from the type itself, and the pointers will be used when they
are actually used as variables/parameters/returns instead.

This does not break ABI though, which is pretty nice.

Similar to obs_data_has_(user_value|default|autoselect), these allow
library users to distinguish between user config values and default
values

Also remove an unused variable from obs-encoder.c (via clang static
analysis)

Also, revamp the settings dialog code and make it use signals and slots
a bit better.

Reduces needless code repetition and still allows for proper memory
alignment.  Cleans up the code a bit.

add my signal/callback interface from another project, also update license of utility files to ISC 1.3

fixed a bug writing to config files where it would use a brace instead of a bracket when creating a section

fixed locale code, added locale files, made wx use locale files, fixed some bugs, and added platform-specific files to the main program