backtester: Fix selling bug, add planned features list (#722)

* Fixes sell bug. Updates docs. Adds test

* Doc fixes

* reorder and lint

* Lint again!

* Minor improvement to ensure theoretical upsized orders don't exceed portfolio limits

* Fixes test error

* %vamoose!

* Fixes defaulting to int

cmd/documentation/documentation.go

@@ -170,6 +170,11 @@ func main() {
 
 		// Github API missing contributors
 		contributors = append(contributors, []Contributor{
+			{
+				Login:         "tk42",
+				URL:           "https://github.com/tk42",
+				Contributions: 2,
+			},
 			{
 				Login:         "daniel-cohen",
 				URL:           "https://github.com/daniel-cohen",
@@ -251,6 +256,11 @@ func main() {
 				URL:           "https://github.com/CodeLingoBot",
 				Contributions: 1,
 			},
+			{
+				Login:         "blombard",
+				URL:           "https://github.com/blombard",
+				Contributions: 1,
+			},
 		}...)
 
 		if verbose {