#112 add boot parameter minmem for change when to create swp file

[Mantas K]

<mantiena> now morphix tries to create swp file if
there are less than 64 Mb RAM, so why don't be flexible
and don't allow change this value with boot parameter ?
<mantiena> in current situation minimum amount of ram
is hardcoded in basemodule. I think it's better to have
an ability to change this at boot time ;)
<alextreme> well, i agree it could be handy in certain
issues
<alextreme> i'll take a look at it next time i hack
scripts-base

I think we could leave 64 Mb as default if minmem boot
parameter is missing.