WebSubmit: autocompeltion for authors

* Provides an author autocompletion facility for WebSubmit. (closes #2276)

* The author autocompletion interface can easily be configured for each
  submission.

* Author sources can be defined as plugins that return results in JSON.

* Author submission and modification are fully compatible with existing
  BibConvert templates.

* Uses typeahead.js <http://twitter.github.io/typeahead.js/>
  for autocompletion.

Co-authored-by: Harris Tzovanakis <charalampos.tzovanakis@cern.ch>
Co-authored-by: Nikolaos Kasioumis <nikolaos.kasioumis@cern.ch>
Signed-off-by: Nikolaos Kasioumis <nikolaos.kasioumis@cern.ch>
1: D205 Blank line missing between one-line summary and description
2: I102 copyright year is outdated, expected 2014 but got 2011
36:1: E302 expected 2 blank lines, found 1
36: D205 Blank line missing between one-line summary and description
36: D208 Docstring is over-indented
44:68: E227 missing whitespace around bitwise or shift operator
45:19: E201 whitespace after '('
45:49: E202 whitespace before ')'
49:30: E228 missing whitespace around modulo operator
55:1: E302 expected 2 blank lines, found 0
55: D205 Blank line missing between one-line summary and description
55: D208 Docstring is over-indented
66:1: E302 expected 2 blank lines, found 0
66: D400 First line should end with '.', not ':'
66: D205 Blank line missing between one-line summary and description
66: D208 Docstring is over-indented
81:27: E231 missing whitespace after ','
87: D301 Use r""" if any backslashes in a docstring
87: D400 First line should end with '.', not 'n'
87: D205 Blank line missing between one-line summary and description
161:17: E231 missing whitespace after ','
170:18: W601 .has_key() is deprecated, use 'in'
172:18: W601 .has_key() is deprecated, use 'in'
174:18: W601 .has_key() is deprecated, use 'in'
176:18: W601 .has_key() is deprecated, use 'in'
178:18: W601 .has_key() is deprecated, use 'in'
183:21: F821 undefined name 'doctype'
183:18: E203 whitespace before ':'
184:20: F821 undefined name 'action'
184:17: E203 whitespace before ':'
185:17: F821 undefined name 'action'
185:14: E203 whitespace before ':'
185:24: E261 at least two spaces before inline comment
185:25: E262 inline comment should start with '# '
186:18: F821 undefined name 'step'
186:15: E203 whitespace before ':'
187:20: F821 undefined name 'access'
187:17: E203 whitespace before ':'
188:13: E203 whitespace before ':'
189:17: E203 whitespace before ':'
190:14: E203 whitespace before ':'
191:20: E203 whitespace before ':'
192:16: F821 undefined name 'rn'
192:13: E203 whitespace before ':'
193:23: F821 undefined name 'last_step'
193:20: E203 whitespace before ':'
194:26: F821 undefined name 'action_score'
194:23: E203 whitespace before ':'
195:32: E203 whitespace before ':'
197:18: F821 undefined name 'sysno'
198:20: E203 whitespace before ':'
199:23: E203 whitespace before ':'
200:26: F821 undefined name 'Request_Print'
204:19: E201 whitespace after '('
204:54: E202 whitespace before ')'
207:33: E231 missing whitespace after ','
223:12: F821 undefined name 'rn'
223:11: E121 continuation line under-indented for hanging indent
227:9: F841 local variable 'subfield' is assigned to but never used
234:20: E225 missing whitespace around operator
246:77: F821 undefined name 'sysno'
290:27: E127 continuation line over-indented for visual indent
324:5: E303 too many blank lines (2)
336:1: W391 blank line at end of file