Move the API into a subdirectory for ease of imports.

Previously, if users of our code put the API folder in their pyshared
they would have to import it as "humbug.humbug". By moving Humbug's API
into a directory named "humbug" and moving the API into __init__, you
can just "import humbug".

(imported from commit 1d2654ae57f8ecbbfe76559de267ec4889708ee8)

bots/send-nagios-notification

@@ -1,50 +0,0 @@
-#!/usr/bin/env python
-import sys
-import optparse
-from os import path
-
-sys.path.append(path.join(path.dirname(__file__), '..'))
-import humbug
-
-# Nagios passes the notification details as command line options.
-# In Nagios, "output" means "first line of output", and "long
-# output" means "other lines of output".
-parser = optparse.OptionParser()
-parser.add_option('--output',      default='')
-parser.add_option('--long-output', default='')
-for opt in ('type', 'host', 'service', 'state'):
-    parser.add_option('--' + opt)
-(opts, args) = parser.parse_args()
-
-msg = dict(type='stream', to='nagios')
-
-# Set a subject based on the host or service in question.  This enables
-# threaded discussion of multiple concurrent issues, and provides useful
-# context when narrowed.
-#
-# We send PROBLEM and RECOVERY messages to the same subject.
-if opts.service is None:
-    # Host notification
-    thing = 'host'
-    msg['subject'] = 'host %s' % (opts.host,)
-else:
-    # Service notification
-    thing = 'service'
-    msg['subject'] = 'service %s on %s' % (opts.service, opts.host)
-
-# e.g. **PROBLEM**: service is CRITICAL
-msg['content'] = '**%s**: %s is %s' % (opts.type, thing, opts.state)
-
-# The "long output" can contain newlines represented by "\n" escape sequences.
-# The Nagios mail command uses /usr/bin/printf "%b" to expand these.
-# We will be more conservative and handle just this one escape sequence.
-output = (opts.output + '\n' + opts.long_output.replace(r'\n', '\n')).strip()
-if output:
-    # Put any command output in a code block.
-    msg['content'] += ('\n\n~~~~\n' + output + "\n~~~~\n")
-
-client = humbug.Client(
-    email   = 'humbug+nagios@humbughq.com',
-    api_key = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',
-    site    = 'https://staging.humbughq.com')
-client.send_message(msg)