Fix dangling title pointers in contexts.

The context parameters struct was taking a CFFI `char[]` object.  This
object owns its data but was not kept alive itself by the struct so
it could be garbage collected before the parameters struct was used.

Now this string is explicitly kept alive.

Fixes #99

Author: HexDecimal

CHANGELOG.rst

@@ -12,6 +12,9 @@ Deprecated
  - Changed context deprecations to PendingDeprecationWarning to reduce mass
    panic from tutorial followers.
 
+Fixed
+ - Fixed garbled titles and crashing on some platforms.
+
 11.16.0 - 2020-10-23
 --------------------
 Added

tcod/context.py

@@ -401,6 +401,8 @@ def new(
     catch_msg = []  # type: List[str]
     catch_handle = ffi.new_handle(catch_msg)  # Keep alive.
 
+    title_p = _handle_title(title)  # Keep alive.
+
     params = ffi.new(
         "struct TCOD_ContextParams*",
         {
@@ -415,7 +417,7 @@ def new(
             "tileset": _handle_tileset(tileset),
             "vsync": vsync,
             "sdl_window_flags": sdl_window_flags,
-            "window_title": _handle_title(title),
+            "window_title": title_p,
             "argc": len(argv_c),
             "argv": argv_c,
             "cli_output": ffi.addressof(lib, "_pycall_cli_output"),