add tinyfiledialog lib for linux dialogs

.gitmodules

@@ -1,60 +1,84 @@
 [submodule "libs/glm"]
 	path = libs/glm
 	url = https://github.com/g-truc/glm.git
+    branch = master
 [submodule "libs/stb/stb"]
 	path = libs/stb/stb
 	url = https://github.com/nothings/stb.git
+    branch = master
 [submodule "libs/yoga"]
 	path = libs/yoga
 	url = https://github.com/facebook/yoga.git
+    branch = master
 [submodule "libs/tinyxml2"]
 	path = libs/tinyxml2
 	url = https://github.com/leethomason/tinyxml2.git
+    branch = master
 [submodule "libs/curl-android-ios"]
 	path = libs/curl-android-ios
 	url = https://bitbucket.org/omigamedev/curl-android-ios.git
+    branch = master
 [submodule "libs/poly2tri"]
 	path = libs/poly2tri
 	url = https://github.com/greenm01/poly2tri
+    branch = master
 [submodule "libs/base64"]
 	path = libs/base64
 	url = https://github.com/tkislan/base64
+    branch = master
 [submodule "libs/bugtrap-client"]
 	path = libs/bugtrap-client
 	url = https://bitbucket.org/omigamedev/bugtrap-client-x64.git
+    branch = master
 [submodule "libs/curl-win"]
 	path = libs/curl-win
 	url = https://bitbucket.org/omigamedev/curl-win64.git
+    branch = master
 [submodule "libs/sqlite3"]
 	path = libs/sqlite3
 	url = https://bitbucket.org/omigamedev/sqlite3.git
+    branch = master
 [submodule "libs/openvr"]
 	path = libs/openvr
 	url = https://github.com/ValveSoftware/openvr.git
+    branch = master
 [submodule "libs/nanort"]
 	path = libs/nanort
 	url = https://github.com/lighttransport/nanort.git
+    branch = master
 [submodule "libs/hash-library"]
 	path = libs/hash-library
 	url = https://github.com/stbrumme/hash-library
+    branch = master
 [submodule "libs/native_app_glue"]
 	path = libs/native_app_glue
 	url = https://bitbucket.org/omigamedev/native_app_glue.git
+    branch = master
 [submodule "libs/fmt"]
 	path = libs/fmt
 	url = https://github.com/fmtlib/fmt.git
+    branch = master
 [submodule "libs/ovr_mobile"]
 	path = libs/ovr_mobile
 	url = https://bitbucket.org/omigamedev/ovr_mobile.git
+    branch = master
 [submodule "libs/ovr_platform"]
 	path = libs/ovr_platform
 	url = https://bitbucket.org/omigamedev/ovr_platform.git
+    branch = master
 [submodule "libs/glad"]
 	path = libs/glad
 	url = https://bitbucket.org/omigamedev/glad.git
+    branch = master
 [submodule "libs/wave_sdk"]
 	path = libs/wave_sdk
 	url = https://bitbucket.org/omigamedev/wave_sdk.git
+    branch = master
 [submodule "libs/appcenter-apple"]
 	path = libs/appcenter-apple
 	url = https://bitbucket.org/omigamedev/appcenter-apple.git
+    branch = master
+[submodule "libs/tinyfiledialogs"]
+	path = libs/tinyfiledialogs
+	url = https://git.code.sf.net/p/tinyfiledialogs/code
+	branch = master