New FAQ file
check for valid coefficients, fixes #210
fix CPLEX sos test
Merge pull request #211 from JuliaOpt/nancheck

check for valid coefficients, fixes #210
tidy GenericAffExpr operators
definition is only safe if applied to instance of the same type
try to avoid try
Merge pull request #206 from JuliaOpt/no-try-catch

RFC: Try to avoid try
Remove another crazy old export
clear internal model if we change something we're not supposed to
Merge pull request #207 from JuliaOpt/prob-mod-fix

RFC: Clear internal model if problem modification won't catch it
remove another pesky try/catch block
make Variable immutable (why not)
modernize vector_speedtest.
close #99
support for quadratic macros.
add quad macro tests
update NEWS
simplify Model constructor.
even simpler Model constructor.
a few more methods for #99.