Increasing the values of 3 constants that control how much space is reserved

Increasing the values of 3 constants that control how much space is reserved
for the stack and/or static memory for holding arrays of structures.
MAX_ORIGINAL_EDGES changed from 0x10000 to 0x20000 (x2 increase).
MAX_MAP_BRUSHES changed from 0x8000 to 0x10000 (x2 increase).
MAX_MAP_DRAW_VERTS changed from 0x80000 to 0x100000 (x2 increase).
This is pertaining to q3map2 only.
There is a real-world case where increasing these constants is needed.
That case is when compiling Icy World for Urban Terror.
Besides that, increasing these does not hurt anything (other than requiring
more memory).

git-svn-id: https://zerowing.idsoftware.com/svn/radiant/GtkRadiant/trunk@422 8a3a26a2-13c4-0310-b231-cf6edde360e5