Fixed issue where file size formatted values would be displayed as zero.

This was caused by an bug present in Jinja:
https://github.com/mitsuhiko/jinja2/pull/59
Added the possibility to pass a pattern (e.g /var/log/**/*.log) when adding log files through the arg option --log.
Escape any HTML tag in the log search response.
Use UTF-8 to decode logs.
Merge pull request #12 from aumo/log_search_html_escaping

HTML in  a log is not escaped when searching it
Merge pull request #13 from aumo/log_searching_and_non_ascii_chars

Exception thrown when searching a log containing non-ASCII characters
Made a quick non-ascii sweep through, may still be a few left.

May need to look at a better way of achieving this further along the way.
Merge remote-tracking branch 'origin/master'
Added a note about newer pip behaviour.

Since https://github.com/pypa/pip/issues/1423 it is no longer allowed to
install packages that are not hosted on PyPI itself by default. It can
be allowed on a per-package basis with the --allow-externals PACKAGE
option.
Since the latest argparse tarball comes from google code, it is
necessary to use --allow-externals for the argparse dependency.
Enforced a line break
Merge pull request #15 from mriehl/docu/pip-allow-externals

Docu/pip allow externals
v0.2.0
Added # coding=utf-8 in net.py
Merge pull request #17 from kracekumar/patch-2

Added # coding=utf-8 in net.py
Changed to 4 space indentation for the css file.
Added a PSDASH_URL_PREFIX configuration setting to allow psdash to be served from a sub-url rather than always on root.