major refactoring to allow proper testing

This commit includes:
* Reducing complexity of modules
* Remove unneeded wrapper classes
* Implement init() for each module which
  initializes everything based on the config
* Implement some basic tests

misc.py

@@ -0,0 +1,57 @@
+
+# Required json-schema for user specified config
+conf_schema = {
+    'type': 'object',
+    'properties': {
+        'max_open_trades': {'type': 'integer'},
+        'stake_currency': {'type': 'string'},
+        'stake_amount': {'type': 'number'},
+        'dry_run': {'type': 'boolean'},
+        'minimal_roi': {
+            'type': 'object',
+            'patternProperties': {
+                '^[0-9.]+$': {'type': 'number'}
+            },
+            'minProperties': 1
+        },
+        'poloniex': {'$ref': '#/definitions/exchange'},
+        'bittrex': {'$ref': '#/definitions/exchange'},
+        'telegram': {
+            'type': 'object',
+            'properties': {
+                'enabled': {'type': 'boolean'},
+                'token': {'type': 'string'},
+                'chat_id': {'type': 'string'},
+            },
+            'required': ['enabled', 'token', 'chat_id']
+        }
+    },
+    'definitions': {
+        'exchange': {
+            'type': 'object',
+            'properties': {
+                'enabled': {'type': 'boolean'},
+                'key': {'type': 'string'},
+                'secret': {'type': 'string'},
+                'pair_whitelist': {
+                    'type': 'array',
+                    'items': {'type': 'string'},
+                    'uniqueItems': True
+                }
+            },
+            'required': ['enabled', 'key', 'secret', 'pair_whitelist']
+        }
+    },
+    'anyOf': [
+        {'required': ['poloniex']},
+        {'required': ['bittrex']}
+    ],
+    'required': [
+        'max_open_trades',
+        'stake_currency',
+        'stake_amount',
+        'dry_run',
+        'minimal_roi',
+        'telegram'
+    ]
+}