[ NNStreamer ] disable nnstreamer trainer

Describe a commit content (Until 80 colums per line) in detail ASAP.

**Changes proposed in this PR:**
- Added TOC generator for README.md

Resolves:

**Self evaluation:**
1. Build test:	 [X]Passed [ ]Failed [ ]Skipped
2. Run test:	 [X]Passed [ ]Failed [ ]Skipped

Signed-off-by: jijoong.moon <jijoong.moon@samsung.com>

nnstreamer/meson.build

@@ -3,5 +3,5 @@ if get_option('enable-nnstreamer-tensor-filter').enabled()
   subdir('tensor_filter')
 endif
 if get_option('enable-nnstreamer-tensor-trainer').enabled()
-  subdir('tensor_trainer')
+#  subdir('tensor_trainer')
 endif

packaging/nntrainer.spec

@@ -1,7 +1,7 @@
 # Execute gbs with --define "testcoverage 1" in case that you must get unittest coverage statistics
 %define         use_cblas 1
 %define         nnstreamer_filter 1
-%define         nnstreamer_trainer 1
+%define         nnstreamer_trainer 0
 %define         nnstreamer_subplugin_path /usr/lib/nnstreamer
 %define         use_gym 0
 %define         support_ccapi 1