LPS-45585 Reduce the DL_FILE_INDEXING_MAX_SIZE property value to  1Mb by default

Hey @laszlocsontos,

cc / @ealonso , @rotty3000 

During  the las week in Madrid @rotty3000 told us about this bug and suggeested us a fix for this. (see https://github.com/rotty3000/liferay-portal/pull/431#issuecomment-40025522)

Can you test it???

Thanks!!