exclude files that are not expected to be visible in the doc or not directly (#1806)

it prenvets some pages like developer/ and community/ pages that are not linked
in the nav but we did not decided yet what to do with to appear in the doc
search.

Files like includes for test accounts also don't have any reason to be accessed
directly.
Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

docs/requirements.txt

@@ -6,3 +6,4 @@ markdown-fenced-code-tabs>=1.0
 markdown-include>=0.5
 MarkupSafe>=1.1
 mkdocs-markdownextradata-plugin==0.0.5
+mkdocs-exclude==1.0.2

mkdocs.yml

@@ -185,3 +185,8 @@ markdown_extensions:
 plugins:
     - search
     - markdownextradata
+    - exclude:
+        glob:
+          - development/*
+          - community/*
+          - global/*