Refactor host configuration handling and script definition creation

so it is possible now to create custom host configuration with template
and all configurations are handled consistenly.
Also introduce and use new ScriptDefinition class wrapping compilation
and evaluation configurations, that could be consistenly created from a
template.

libraries/scripting/jvm-host-test/test/kotlin/script/experimental/jvmhost/test/ScriptingHostTest.kt

@@ -54,12 +54,11 @@ class ScriptingHostTest : TestCase() {
         val greeting = "Hello from script!"
         val output = captureOut {
             val basicJvmScriptingHost = BasicJvmScriptingHost()
-            basicJvmScriptingHost.eval(
+            basicJvmScriptingHost.evalWithTemplate<SimpleScript>(
                 "println(\"$greeting\")".toScriptSource("name"),
-                createJvmCompilationConfigurationFromTemplate<SimpleScript>(basicJvmScriptingHost.hostConfiguration) {
+                compilation = {
                     updateClasspath(classpathFromClass<SimpleScript>())
-                },
-                createJvmEvaluationConfigurationFromTemplate<SimpleScript>(basicJvmScriptingHost.hostConfiguration)
+                }
             ).throwOnFailure()
         }
         Assert.assertEquals(greeting, output)
@@ -206,15 +205,19 @@ class ScriptingHostTest : TestCase() {
     fun testSimpleImportWithImplicitReceiver() {
         val greeting = listOf("Hello from helloWithVal script!", "Hello from imported helloWithVal script!")
         val script = "println(\"Hello from imported \$helloScriptName script!\")"
-        val compilationConfiguration = createJvmCompilationConfigurationFromTemplate<SimpleScriptTemplate> {
-            makeSimpleConfigurationWithTestImport()
-            implicitReceivers(String::class)
-        }
-        val evaluationConfiguration = createJvmEvaluationConfigurationFromTemplate<SimpleScriptTemplate> {
-            implicitReceivers("abc")
-        }
+        val definition = createJvmScriptDefinitionFromTemplate<SimpleScriptTemplate>(
+            compilation = {
+                makeSimpleConfigurationWithTestImport()
+                implicitReceivers(String::class)
+            },
+            evaluation = {
+                implicitReceivers("abc")
+            }
+        )
         val output = captureOut {
-            BasicJvmScriptingHost().eval(script.toScriptSource(), compilationConfiguration, evaluationConfiguration).throwOnFailure()
+            BasicJvmScriptingHost().eval(
+                script.toScriptSource(), definition.compilationConfiguration, definition.evaluationConfiguration
+            ).throwOnFailure()
         }.lines()
         Assert.assertEquals(greeting, output)
     }