add speculations and tests
add speculation limit signal
add signals
merge
fix all bugs due to merge
some fix
rename SpeculationOrder into CorporationSpeculationOrder
add DerivativeSpeculationOrder
fix some bugs
fix some bugs
fix some bugs and add describe
add commentaries
fix signals
Merge branch 'master' of github.com:Neamar/corporate into speculations

Conflicts:
	corporate/settings.py
lots of fix
add constants
fix comments
some fix
some fix
Merge branch 'master' into speculations