put in retries when aleph hits git

[dollschasingmen]

we see rare and temporary issues like this -- a surgical retry might mitigate this.

one important note: Aleph already uses a retrying lib called Pester so we should use that.

related trace that alerted us to this issue:
OpenSSL::SSL::SSLErrorWaitReadable: read would block

• 15 non-project frames
  16
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github.rb" line 46 in send_request
  17
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github.rb" line 54 in post
  18
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/tree.rb" line 24 in create
  19
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/pusher.rb" line 44 in create_tree
  20
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/pusher.rb" line 72 in git_push
  21
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/models/query_version.rb" line 55 in github_save
• 73 non-project frames
  95
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/interaction/query_update.rb" line 42 in execute
  96
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/controllers/queries_controller.rb" line 44 in block (2 levels) in update
• 2 non-project frames
  99
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/controllers/queries_controller.rb" line 41 in update
• 80 non-project frames
  Net::ReadTimeout: Net::ReadTimeout
• 14 non-project frames
  15
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github.rb" line 46 in send_request
  16
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github.rb" line 54 in post
  17
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/tree.rb" line 24 in create
  18
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/pusher.rb" line 44 in create_tree
  19
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/github/pusher.rb" line 72 in git_push
  20
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/models/query_version.rb" line 55 in github_save
• 73 non-project frames
  94
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/lib/interaction/query_update.rb" line 42 in execute
  95
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/controllers/queries_controller.rb" line 44 in block (2 levels) in update
• 2 non-project frames
  98
  File "/usr/local/bundle/gems/aleph_analytics-0.1.0/app/controllers/queries_controller.rb" line 41 in update

[apurvis]

#75