Changed replaceable components for heat transfer in Flow1DXX to replaceable classes

git-svn-id: https://thermopower.svn.sourceforge.net/svnroot/thermopower/trunk@282 80daafeb-7430-0410-91d5-8b30b0bbd841
Started adding new initialization options and system default

git-svn-id: https://thermopower.svn.sourceforge.net/svnroot/thermopower/trunk@283 80daafeb-7430-0410-91d5-8b30b0bbd841
Fix provided by Adrian Pop

git-svn-id: https://thermopower.svn.sourceforge.net/svnroot/thermopower/trunk@284 80daafeb-7430-0410-91d5-8b30b0bbd841
Updated System object

git-svn-id: https://thermopower.svn.sourceforge.net/svnroot/thermopower/trunk@285 80daafeb-7430-0410-91d5-8b30b0bbd841