Misc. formatting improvements for gwdetchar-omega

[alurban]

@duncanmmacleod, this PR contains a few formatting enhancements for gwdetchar-omega output pages, including:

• Restoring IFO-specific context highlighting in plot toggle buttons
• Expand container width and adapt its size for different screens
• Reorganizing the channel information display so that the channel name is on its own line, plot toggle buttons are flushed right on the same line as the loudest-tile table (which is now horizontal), and up to three plots are shown on a single line beneath the table
• De-bolden section headings (which will need to be done more gracefully once gwdetchar-omega should use bootstrap-ligo for CSS helpers #90 is addressed)
• Update the output page after every channel has been analyzed, as well as after every channel block, and once again at the very end

Examples may be found here (requires LIGO.ORG credentials):

IFO	Scan time	Results
Hanford	1187020580.44	results
Livingston	1172489783.070	results
GEO	1186970418.0	results

This fixes #122.

[coveralls]

Pull Request Test Coverage Report for Build 308

• 0 of 30 (0.0%) changed or added relevant lines in 2 files are covered.
• 4 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.2%) to 40.263%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
gwdetchar/omega/plot.py	0	2	0.0%
gwdetchar/omega/html.py	0	28	0.0%

Files with Coverage Reduction	New Missed Lines	%
gwdetchar/omega/plot.py	1	0.0%
gwdetchar/omega/html.py	3	0.0%

Totals
Change from base Build 305:	-0.2%
Covered Lines:	428
Relevant Lines:	1063

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💛 - Coveralls

[alurban]

@duncanmmacleod, I've pushed a few commits that address your review comments. I also reorganized the layout for each channel so that the table of loudest-tile properties is horizontal at the top, aligned with the toggle buttons, and a row of three plots is saved at the bottom. The examples for H1 and L1 linked to above have been updated with these changes.