[CORDA-2235]: Add overrides for network parameters via command line and file (#4279)

* Temp commit

* Print the error message first by default, makes error output more natural.

* Polishing

* Further modifications after testing

* Documentation updates

* Couple of fixes after review

* Removing unnecessary tests

* Fix broken test

* Add interface to bootstrapper for testign

* Added unit tests

* Remove unused class

* Fix up bootstrapper unit tests and add a couple more

* Refactor the tests slightly

* Review comments

* Couple of minor tweaks

common/configuration-parsing/src/main/kotlin/net/corda/common/configuration/parsing/internal/Configuration.kt

@@ -448,7 +448,7 @@ object Configuration {
 
             override fun toString(): String {
 
-                return "(keyName='$keyName', typeName='$typeName', path=$path, message='$message')"
+                return "$message: (keyName='$keyName', typeName='$typeName', path=$path)"
             }
 
             /**