(Exchanges) Introduce validation method and small updates (#565)

* Remove pointer reference

* Fix portfolio withdraw tests

* Add nil protection in validator method to reduce prospective panics and for future outbound checking

* Updated tests

* ch order var to not ref package

* rm comparison

* Add order ID validation check

* Add exchange name validation check

* Add in test details

* fix tests

* fix linter issues

* linter issues strikes again

* linter rabbit hole

* Addr nitterinos

* Add validation variadic interface to define sets of functionality check POC

* didn't want to add an amount other than 0, didn't want to add address to exchange withdraw, didn't want to whitlist, can change if need be

* add coverage

* Add validation method options for exchange wrappers and abstracted validation into its own package

* Add validation code for structs in exchange template generation

* remove extra validation call as this is done in wrapper

* fix niterinos for examplerinos

* Add template to documentation tool and regenerated documentation

* Addr niticles

* Fix tests due to validation update

* Add more validation checks for modify/submit orders

* update tests

* fix more tests

* Add asset type to submit variable in tests and rpc call. Regen funcs.

* Add field to modify struct in tests

* applied field asset to cancel struct across project

* fix woopsy

cmd/documentation/documentation.go

@@ -169,8 +169,11 @@ func main() {
 
 		// Github API missing contributors
 		contributors = append(contributors, []Contributor{
-			// idoall's contributors were forked and merged, so his contributions
-			// aren't automatically retrievable
+			{
+				Login:         "daniel-cohen",
+				URL:           "https://github.com/daniel-cohen",
+				Contributions: 1,
+			},
 			{
 				Login:         "DirectX",
 				URL:           "https://github.com/DirectX",
@@ -181,6 +184,8 @@ func main() {
 				URL:           "https://github.com/frankzougc",
 				Contributions: 1,
 			},
+			// idoall's contributors were forked and merged, so his contributions
+			// aren't automatically retrievable
 			{
 				Login:         "idoall",
 				URL:           "https://github.com/idoall",

cmd/documentation/exchanges_templates/validate.tmpl

@@ -0,0 +1,78 @@
+{{define "exchanges validate" -}}
+{{template "header" .}}
+## Current Features for {{.Name}}
+
++ This package allows for validation options to occur exchange side e.g.
+  - Checking for ID in an order cancellation struct.
+  - Determining the correct withdrawal bank details for a specific exchange.
+
++ Example Usage below:
+
+```go 
+// import package
+"github.com/thrasher-corp/exchanges/validate"
+
+// define your data structure across potential exchanges
+type Critical struct {
+    ID string
+    Person string
+    Banks string
+    MoneysUSD float64
+}
+
+// define validation and add a variadic param
+func (supercritcalinfo *Critical) Validate(opt ...validate.Checker) error {
+    // define base level validation
+    if supercritcalinfo != nil {
+        // oh no this is nil, could panic program!
+    }
+
+    // range over potential checks coming from individual packages
+    var errs common.Errors
+	for _, o := range opt {
+		err := o.Check()
+		if err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	if errs != nil {
+		return errs
+	}
+    return nil
+}
+
+// define an exchange or package level check that returns a validate.Checker 
+// interface
+func (supercritcalinfo *Critical) PleaseDontSendMoneyToParents() validate.Checker {
+    return validate.Check(func() error {
+		if supercritcalinfo.Person == "Mother Dearest" ||
+        supercritcalinfo.Person == "Father Dearest" {
+        return errors.New("nope")
+    }
+    return nil
+	})
+}
+
+
+// Now in the package all you have to do is add in your options or not...
+d := Critical{Person: "Mother Dearest", MoneysUSD: 1337.30}
+
+// This should not error 
+err := d.Validate()
+if err != nil {
+    return err
+}
+
+// This should error 
+err := d.Validate(d.PleaseDontSendMoneyToParents())
+if err != nil {
+    return err
+}
+
+```
+
+### Please click GoDocs chevron above to view current GoDoc information for this package
+{{template "contributions"}}
+{{template "donations" .}}
+{{end}}