Allow comparing of string literals in IF, WHEN.. THEN and UNTIL.
Add UNSET command. Passing ALL removes all user-defined vars, can also unset specific variables. Implements #261.
Special Value is abstract
added Lists
list can be queried by index
Changed node ETA to be settable
nodes can now change their ETA
WIP control flow
Merge remote-tracking branch 'a1270/stringliteralsfix'
finished FOR Command
Merge remote-tracking branch 'a1270/unsetcommand'
cleanup for release
revered node DELTAV to previous behavior
Update ExpressionTerm.cs

enables scientific notation eg 6.6E-11 -> 6.6*10^-11
Update ExpressionTerm.cs

* better regex, exactly one + or - after an upper E and at least one digit afterwards
Merge pull request #1 from enkido/master

Adding Support for E Notation. Thanks enkido!
loop slow down fix

excution time of command blocks in loops increases with time
added, moved  some stats

*moved orbit stats to the orbit object (accessible via ship and ship
target)
*added body stats from JackDTaylor
robust load behavior
added Close Terminal Action