Added an $On Ship Arrive scripting hook.

git-svn-id: svn://svn.icculus.org/fs2open@10188 387891d4-d844-0410-90c0-e4c51a9137d3
Trunk sync r10188.

git-svn-id: svn://svn.icculus.org/fs2open@10189 387891d4-d844-0410-90c0-e4c51a9137d3
fix hidden divide-by-zero

git-svn-id: svn://svn.icculus.org/fs2open@10190 387891d4-d844-0410-90c0-e4c51a9137d3
Made +delay, +reverse_delay and +acceleration in animation code optional and default to 0.

git-svn-id: svn://svn.icculus.org/fs2open@10191 387891d4-d844-0410-90c0-e4c51a9137d3
Made +delay and +acceleration in animation code optional and default to 0.

git-svn-id: svn://svn.icculus.org/fs2open@10192 387891d4-d844-0410-90c0-e4c51a9137d3
Enabled fighterbay door animations to better define which bay path must be used or not used for the animation to trigger using +sub_type. Fixes the (undocumented) current numbering of fighterbay +sub_types to be 1-based instead of 0-based. Turns the SUBTYPE_CHECK macro to a proper function.

git-svn-id: svn://svn.icculus.org/fs2open@10193 387891d4-d844-0410-90c0-e4c51a9137d3
Enabled fighterbay door animations to better define which bay path must be used or not used for the animation to trigger using +sub_type. Fixes the (undocumented) current numbering of fighterbay +sub_types to be 1-based instead of 0-based. Turns the SUBTYPE_CHECK macro to a proper function.

git-svn-id: svn://svn.icculus.org/fs2open@10194 387891d4-d844-0410-90c0-e4c51a9137d3