add git, bash to conda env (#322)

* add git, bash to conda env

allows to download COCO dataset and run .sh scripts

* review feedback: add missing curl,unzip for COCO dataset

add missing dependencies for COCO download script.

environment.yml

@@ -7,6 +7,7 @@
 name: yolact-env
 #prefix: /your/custom/path/envs/yolact-env
 channels:
+  - conda-forge
   - pytorch
   - defaults
 dependencies:
@@ -19,6 +20,10 @@ dependencies:
   - cudnn
   - pytorch::cuda100
   - matplotlib
+  - git # to download COCO dataset
+  - curl # to download COCO dataset
+  - unzip # to download COCO dataset
+  - conda-forge::bash # to download COCO dataset
   - pip:
     - opencv-python 
     - pillow <7.0 # bug PILLOW_VERSION in torchvision, must be < 7.0 until torchvision is upgraded