Update custom tms code example (#771)

Author: GeoWill

docs/src/examples/code/tiler_with_custom_tms.md

@@ -20,15 +20,14 @@ from pyproj import CRS
 EPSG6933 = TileMatrixSet.custom(
     (-17357881.81713629, -7324184.56362408, 17357881.81713629, 7324184.56362408),
     CRS.from_epsg(6933),
-    identifier="EPSG6933",
+    id="EPSG6933",
     matrix_scale=[1, 1],
 )
-
 # 2. Register TMS
-tms = tms.register([EPSG6933])
+tms = tms.register({EPSG6933.id:EPSG6933})
 
-tms = TMSFactory(supported_tms=tms)
-cog = TilerFactory(supported_tms=tms)
+tms_factory = TMSFactory(supported_tms=tms)
+cog_factory = TilerFactory(supported_tms=tms)
 ```
 
 2 - Create app and register our custom endpoints
@@ -44,11 +43,11 @@ from titiler.core.errors import DEFAULT_STATUS_CODES, add_exception_handlers
 
 from fastapi import FastAPI
 
-from .routes import cog, tms
+from .routes import cog_factory, tms_factory
 
 app = FastAPI(title="My simple app with custom TMS")
 
-app.include_router(cog.router, tags=["Cloud Optimized GeoTIFF"])
-app.include_router(tms.router, tags=["Tiling Schemes"])
+app.include_router(cog_factory.router, tags=["Cloud Optimized GeoTIFF"])
+app.include_router(tms_factory.router, tags=["Tiling Schemes"])
 add_exception_handlers(app, DEFAULT_STATUS_CODES)
 ```