Simple Python Script:
import os
SOURCE_ROOT = "ROOT DIRECTORY - WILL CONVERT ALL UNDERNEATH"
for root, dirs, files in os.walk(SOURCE_ROOT):
for f in files:
fpath = os.path.join(root,f)
assert os.path.exists(fpath)
data = open(fpath, "r").read()
data = data.replace(" ", "\t")
outfile = open(fpath, "w")
outfile.write(data)
outfile.close()