add feature hashing and py2.7 support

- Support feature hashing on the fly in training and inference process example
- Add python2.7 support
- Refactor methods in input_embedding.py
- Refactor layers and models

Author: 浅梦

.travis.yml

@@ -3,10 +3,11 @@
 language: python
 
 python:
+  - "2.7"
   - "3.4"
   - "3.5"
   - "3.6"
-#  - "3.7"
+  #- "3.7"
 
 env:
 #  - TF_VERSION=1.13.1
@@ -15,14 +16,16 @@ env:
   #Not Support- TF_VERSION=1.7.0
   #Not Support- TF_VERSION=1.7.1
   #Not Support- TF_VERSION=1.8.0
-  - TF_VERSION=1.9.0
+  #- TF_VERSION=1.8.0
   - TF_VERSION=1.10.0 #- TF_VERSION=1.10.1
   #    - TF_VERSION=1.11.0
-  - TF_VERSION=1.5.1 #- TF_VERSION=1.5.0
+  #- TF_VERSION=1.5.1 #- TF_VERSION=1.5.0
   - TF_VERSION=1.6.0
 
 matrix:
   allow_failures:
+    - python: "2.7"
+      env: TF_VERSION=1.6.0 # to speed up
     - python: "3.4"
     - python: "3.5"
     - python: "3.7"

deepctr/__init__.py

@@ -1,6 +1,6 @@
 from . import layers
 from . import models
-from .utils import check_version, SingleFeat, VarLenFeat
+from .utils import check_version
 
-__version__ = '0.3.4'
+__version__ = '0.4.0'
 check_version(__version__)