Case-sensitive fix for ToE/Toe in GLONASS ephemeris

[ammtc]

Since MATLAB and many OSes are case-sensitive, all references to "ToE" in the GLONASS ephemeris should be written as "Toe" to simplify/unify the user experience with respect to the various navsu functions.

This quantity is referred to as "Toe" consistently throughout RINEX 3.4 (and the same goes for "Toc"), with the exception of some explanatory (and thus non-binding) text in Section 6.13. It is not mentioned at all by this label in either the current or draft revised versions [1][2][3][4] of the GLONASS ICD.