sdbus++: use consistent typenames for properties

Previously, the generated code was assuming C++ names, but the example
(Calculator.interface.yaml) used an arbitrary name ('integer').  This
commit defines a consistent typename scheme and validates it when
interfaces are generated.

Use English typenames from the DBus protocol in interface files
rather than the C++ name or a single-letter DBus name.  Use
square-bracket ([]) to identify sub-types for containers.

Examples: 'int64', 'path', 'array[dict[string, byte]]'

Change-Id: I38abe84c9cd3d5f839968349d2d3cfa0b8796cd0
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/tools/example/net/poettering/Calculator.interface.yaml b/tools/example/net/poettering/Calculator.interface.yaml
index 2c288b6..4167c36 100644
--- a/tools/example/net/poettering/Calculator.interface.yaml
+++ b/tools/example/net/poettering/Calculator.interface.yaml
@@ -8,17 +8,17 @@
         Multiplies two integers 'x' and 'y' and returns the result.
       parameters:
         - name: x
-          type: integer
+          type: int64
           description: >
             The first integer to multiply.
         - name: y
-          type: integer
+          type: int64
           description: >
             The second integer to multiply.
           default: 1
       returns:
         - name: z
-          type: integer
+          type: int64
           description: >
             The result of (x*y).
     - name: Divide
@@ -26,17 +26,17 @@
         Divides two integers 'x' and 'y' and returns the result.
       parameters:
         - name: x
-          type: integer
+          type: int64
           description: >
             The first integer to divide.
         - name: y
-          type: integer
+          type: int64
           description: >
             The second integer to divide.
           default: 1
       returns:
         - name: z
-          type: integer
+          type: int64
           description: >
             The result of (x/y).
       errors:
@@ -46,7 +46,7 @@
         Reset the LastResult property to zero.
 properties:
     - name: LastResult
-      type: integer
+      type: int64
       default: 0
       description: >
         The result of the most recent calculation.
@@ -56,7 +56,7 @@
         Signal indicating the LastReset property has been set to zero by the
         'Clear' method.
       properties:
-        - type: integer
+        - type: int64
           description: >
             Value of LastReset prior to Clear.