PHP page for accepting new or updated observations
Merge pull request #50 from jmfee-usgs/GMP-288

Merging code from emmerichc-usgs, will be another pull request for any changes after further review.
Added markup for Declination View.
Created Sass file for Declination View, added some styles
Merged conflict in SCSS file
Added meanMark function to ObservationBaselineCalculator based on _mean from BaselineCalculator
Resolved merge conflict with ANGLE_FACTOR
Changed default value for angle from null to 0.
Shortened most variable names to fit in 80 column width
Added handler to trigger mark-selected to autofill values & other small fixes
Added mean functions for meanMark, meanH, meanE, meanZ & meanD. Also, changed most references from observation to observatory when working with piers & marks.
Added bindings to update values automatically on file load by watching mark
Refactored & organized code.
Changed table into a definition list, updated styles accordingly
Renamed to use as a partial
Rolled back declination changes, submitting fixes only
Updated OBSERVATION to OBSERVATORY
Added rewrite for default mount path
Select default pier and mark in collections while parsing
changed to extend Model; pierCorrection and trueAzimuthOfMark are part of model and default to 0; removed observatory parameter from methods.