Language center fixes

• Fixed faculty resolving. Previously, some enrollments/credits were filtered out erroneously due to not finding a faculty. Now the faculties are found more accurately, and some miscellaneous faculties are bundled into "Other faculties" column. This increased the numbers, especially in the "Open uni" column.
• Removed total row when in ratio-mode. It is not very useful due to enrollments missing from some courses/semester, which caused all the total row cells to show 100%.
• Changed a mention of "credits" to "completions" in the number mode selector