Contributions to 1.2.7

[rogerfraser]

This pull request contributes several fixes and enhancements scheduled for version 1.27, and specifically addresses the following issues:

• Create the ability to add in Type B positional uncertainties after adjustment #31
• Default Reference Frame in User's Guide #80
• geoid.exe --text-file mode: ‘default’ direction is documented incorrectly (v 1.2.6, 06 SEPT) #185
• geoid.exe --verbose option does NOT currently result in a log file. (Does this affect other DynAdjust exe too?) (v 1.2.6, 06 SEPT)  #186
• geoid.exe --verbose option: Request for command line reference to indicate that output is to be directed to log file. (v 1.2.6, 06 SEPT)  #187
• geoid.exe --text-file mode echoes the datum reported in geoid metadata (whether correct or not) (v 1.2.6, 06 SEPT)  #188
• geoid.exe: Request for more instruction on input text file formats in command line referencing (v 1.2.6, 06 SEPT) #189
• geoid.exe --text-file mode: should report the direction for conversion of heights. (v 1.2.6, 06 SEPT) #190
• Minor typographic errors #191
• Update 'Skye' tutorial documentation to reflect changes to code, defaults, and SampleData (v 1.2.6, 06 SEPT)  #193
• Unexpected behaviour in reftran.exe MeasurementIDs removed #203
• Add support for ITRF2020 #206