Bugfix and feature fork for ua's Aegisub scripts

Manuals for all scripts: https://unanimated.github.io/ts/scripts-manuals.htm

Changelog:

• Snap [Bugfix]: JoinSplitSnap will now snap to the closest keyframe if there are multiple keyframes in range.
• Snap [Feature]: You can now snap the start and the end of a line separately.
• Blur And Glow [Bugfix]: BlurAndGlow will no longer return out-of-bounds selected_lines when only add glow is selected.
• NecrosCopy [Bugfix]: clip2frz and clip2fax will now accept subpixel clips thanks to @petzku's commit 2d3a40.
• NecrosCopy [Bugfix]: clip2fax now generates \fax with 4 digits after decimal point.
• Significance [Bugfix]: When exporting chapters, Significance no longer changes timestamp from 00:00:00.000 to 00:00:00.033.
• Significance [Feature]: Add export xml and txt as when exporting chapters.
• Cycles [Feature]: Cycles can now be edited inside Aegisub using aka.config.

Other information:

• HYDRA [Note]: PhosCity has a script called Edit Tags that functions more or less similar to HYDRA but it will prefill the tags on the selected line when you open the GUI which is pretty convenient.