Makes FontData importable resource.

Adds multi-channel SDF font texture generation and rendering support.
Adds per-font oversampling support.
Adds FontData import plugins (for dynamic fonts, BMFonts and monospaced image fonts), font texture cache pre-generation and loading.
Adds BMFont binary format and outline support.

modules/text_server_adv/SCsub

@@ -38,7 +38,8 @@ def make_icu_data(target, source, env):
 # Thirdparty source files
 
 thirdparty_obj = []
-freetype_enabled = env.module_check_dependencies("text_server_adv", ["freetype"])
+freetype_enabled = env.module_check_dependencies("text_server_adv", ["freetype"], True)
+msdngen_enabled = env.module_check_dependencies("text_server_adv", ["msdfgen"], True)
 
 if env["builtin_harfbuzz"]:
     env_harfbuzz = env_modules.Clone()
@@ -509,6 +510,13 @@ env_text_server_adv.Append(
     ]
 )
 
+if msdngen_enabled:
+    env_text_server_adv.Append(
+        CPPPATH=[
+            "#thirdparty/msdfgen",
+        ]
+    )
+
 if freetype_enabled:
     env_text_server_adv.Append(
         CPPPATH=[