Implemented some enhancement request and fixed some bugs

Fixed #2 : Variables are not recognized when inside a rule token
Fixed #15 : Rule: rete attributes are lost when a new ontology is created
Fixed #14 : ReteNetwork: Format rules must not be added to Rete network
Fixed #16 : DefConcept: Variables are not recognized when they are keyword arguments
Fixed #4 : Comparison are not correctly set when comparison property is a concept
Fixed #14 : Parser: merge FunctionParser.NamesNode and ExpressionParser.NamesNode
Fixed #18 : Parser: Add SourceCodeNode test to UnrecognizedNodeParser
Fixed #20 : At startup Number concept is saved in db a numerous number of time
Fixed #21 : CacheManager: I can remove all elements from a ListIfNeededCache and fill it again
Fixed #22 : CacheManager: I can remove all elements from a SetCache and fill it again
Fixed #23 : HistoryManager: history() no longer works
Fixed #24 : HistoryManager: history() no longer works after creating an exec rule
Fixed #25 : SheerkaMemory: Use MemoryObject instead of sheerka.local
Fixed #26 : Debugger: add the list all available services..
Fixed #27 : CONCEPTS_GRAMMARS_ENTRY does not seems to be in use any more
Fixed #28 : Give order to services

src/parsers/ExpressionParser.py

@@ -1,8 +1,7 @@
 from itertools import product
 
 from core.builtin_concepts import BuiltinConcepts
-from core.builtin_helpers import only_successful, parse_unrecognized, get_inner_body, parse_python, \
-    get_lexer_nodes_using_positions
+from core.builtin_helpers import only_successful, get_inner_body, get_lexer_nodes_using_positions
 from core.sheerka.services.SheerkaExecute import ParserInput
 from core.sheerka.services.sheerka_service import FailedToCompileError
 from core.tokenizer import TokenKind, Tokenizer, Keywords
@@ -247,7 +246,7 @@ class ExpressionParser(BaseParser):
         for conjunction in conjunctions:
             # try to recognize conjunction, one by one
             # negative conjunction can be a concept starting with 'not'
-            parsed_ret = parse_unrecognized(
+            parsed_ret = context.sheerka.parse_unrecognized(
                 context,
                 conjunction.get_value(),  # we remove the 'NOT' part when needed to ease the recognition
                 parsers="all",
@@ -280,7 +279,7 @@ class ExpressionParser(BaseParser):
                 return_values.append(recognized_conjunctions[0])
             elif len(recognized_conjunctions) == 1 and recognized_conjunctions[0].who == "parsers.Python":
                 # it is a negated python Node. Need to parse again
-                ret = parse_python(context, source=str(conjunctions[0]))
+                ret = context.sheerka.parse_python(context, source=str(conjunctions[0]))
                 if ret.status:
                     return_values.append(ret)
                 else: