patch 8.0.1773: dialog messages are not translated

Problem:    Dialog messages are not translated.
Solution:   Add N_() and _() where needed. (Sergey Alyoshin)
diff --git a/src/vim.h b/src/vim.h
index 985a492..af01f1a 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -2186,16 +2186,16 @@
 #ifdef FEAT_BROWSE
 # ifdef BACKSLASH_IN_FILENAME
 #  define BROWSE_FILTER_MACROS \
-	(char_u *)"Vim macro files (*.vim)\t*.vim\nAll Files (*.*)\t*.*\n"
-#  define BROWSE_FILTER_ALL_FILES (char_u *)"All Files (*.*)\t*.*\n"
+	(char_u *)N_("Vim macro files (*.vim)\t*.vim\nAll Files (*.*)\t*.*\n")
+#  define BROWSE_FILTER_ALL_FILES (char_u *)N_("All Files (*.*)\t*.*\n")
 #  define BROWSE_FILTER_DEFAULT \
-	(char_u *)"All Files (*.*)\t*.*\nC source (*.c, *.h)\t*.c;*.h\nC++ source (*.cpp, *.hpp)\t*.cpp;*.hpp\nVB code (*.bas, *.frm)\t*.bas;*.frm\nVim files (*.vim, _vimrc, _gvimrc)\t*.vim;_vimrc;_gvimrc\n"
+	(char_u *)N_("All Files (*.*)\t*.*\nC source (*.c, *.h)\t*.c;*.h\nC++ source (*.cpp, *.hpp)\t*.cpp;*.hpp\nVB code (*.bas, *.frm)\t*.bas;*.frm\nVim files (*.vim, _vimrc, _gvimrc)\t*.vim;_vimrc;_gvimrc\n")
 # else
 #  define BROWSE_FILTER_MACROS \
-	(char_u *)"Vim macro files (*.vim)\t*.vim\nAll Files (*)\t*\n"
-#  define BROWSE_FILTER_ALL_FILES (char_u *)"All Files (*)\t*\n"
+	(char_u *)N_("Vim macro files (*.vim)\t*.vim\nAll Files (*)\t*\n")
+#  define BROWSE_FILTER_ALL_FILES (char_u *)N_("All Files (*)\t*\n")
 #  define BROWSE_FILTER_DEFAULT \
-	(char_u *)"All Files (*)\t*\nC source (*.c, *.h)\t*.c;*.h\nC++ source (*.cpp, *.hpp)\t*.cpp;*.hpp\nVim files (*.vim, _vimrc, _gvimrc)\t*.vim;_vimrc;_gvimrc\n"
+	(char_u *)N_("All Files (*)\t*\nC source (*.c, *.h)\t*.c;*.h\nC++ source (*.cpp, *.hpp)\t*.cpp;*.hpp\nVim files (*.vim, _vimrc, _gvimrc)\t*.vim;_vimrc;_gvimrc\n")
 # endif
 # define BROWSE_SAVE 1	    /* flag for do_browse() */
 # define BROWSE_DIR 2	    /* flag for do_browse() */