Loads of changes!

* Added conversion plugins (API might change!)
* Added conversion to the analysis pipeline
* Changed behaviour of --default-plugins (it adds conversion plugins regardless)
* Added emotionModel [sic] and emotionConversion models

//TODO add conversion tests
//TODO add conversion to docs

tests/plugins/dummy_plugin/dummy.py

@@ -0,0 +1,7 @@
+from senpy.plugins import SentimentPlugin
+
+
+class DummyPlugin(SentimentPlugin):
+    def analyse_entry(self, entry, params):
+        entry.text = entry.text[::-1]
+        yield entry

tests/plugins/dummy_plugin/dummy.senpy

@@ -0,0 +1,15 @@
+{
+    "name": "Dummy",
+    "module": "dummy",
+    "description": "I am dummy",
+    "author": "@balkian",
+    "version": "0.1",
+    "extra_params": {
+        "example": {
+            "@id": "example_parameter",
+            "aliases": ["example", "ex"],
+            "required": false,
+            "default": 0
+        }
+    }
+}

tests/plugins/dummy_plugin/dummy_required.senpy

@@ -0,0 +1,14 @@
+{
+    "name": "DummyRequired",
+    "module": "dummy",
+    "description": "I am dummy",
+    "author": "@balkian",
+    "version": "0.1",
+    "extra_params": {
+        "example": {
+            "@id": "example_parameter",
+            "aliases": ["example", "ex"],
+            "required": true
+        }
+    }
+}