general: Elasticsearch logging with Lumberjack.

* Added disabled-by-default config options for Elasticsearch logging.
* Replaced rnkPAGEVIEWS and rnkDOWNLOADS with Elasticsearch.

Signed-off-by: Joe MacMahon <joe.macmahon@cern.ch>
1: D100 Docstring missing
4: I102 copyright year is outdated, expected 2014 but got 2012
21:4: E121 continuation line under-indented for hanging indent
24:6: E126 continuation line over-indented for hanging indent
36:9: E128 continuation line under-indented for visual indent
46:1: E302 expected 2 blank lines, found 1
46: D209 Put multi-line docstring closing quotes on separate line
46: D205 Blank line missing between one-line summary and description
46: D208 Docstring is over-indented
58:21: E261 at least two spaces before inline comment
60:20: E261 at least two spaces before inline comment
65:1: E302 expected 2 blank lines, found 1
65: D400 First line should end with '.', not 'D'
65: D205 Blank line missing between one-line summary and description
65: D208 Docstring is over-indented
82:60: E502 the backslash is redundant between brackets
83:70: E502 the backslash is redundant between brackets
84:63: E502 the backslash is redundant between brackets
87:1: E302 expected 2 blank lines, found 1
87: D400 First line should end with '.', not 'y'
87: D205 Blank line missing between one-line summary and description
87: D208 Docstring is over-indented
98:18: E261 at least two spaces before inline comment
101:10: E261 at least two spaces before inline comment
104:65: E502 the backslash is redundant between brackets
105:56: E502 the backslash is redundant between brackets
106:57: E502 the backslash is redundant between brackets
117:76: E502 the backslash is redundant between brackets
118:47: E502 the backslash is redundant between brackets
119:76: E502 the backslash is redundant between brackets
120:48: E502 the backslash is redundant between brackets