Support all text-based ctypes
Fix "text" ctype in smb_enumshares

"text" is not a valid ctype, should be text/plain
Fix datastore assignments
Fix file handle leak
Um, this is the right way to do it.
Extract query params separately

Prevents stomping on data
Land #3629, @wchen-r7's HTTP traversal fixes
Land #3626, @wchen-r7's storing of text loot as txt
Land #3627, @wchen-r7's cleanup of ctypes in smb_enumshares