simplehttp_log: be paranoid about input_buffer

check and log any possible nulls for or in the input_buffer
Merge pull request #81 from ploxiln/simplehttp_log_paranoid

simplehttp_log: be paranoid about input_buffer
we shoud be skipping not found errors, not 500ing
Merge pull request #82 from mreiferson/404_fix

simpletokyo 500s when any mget key is missing
Document --expected-value-regex in pubsub_filtered README
Merge pull request #83 from jsocol/expected-value-regex_83

document --expected-value-regex param for pubsub_filtered