Creature weight is now tracked as a floating point value

Fixes issue #174
Fixed more lint found by clang static analyzer

char_class.c: Removed extraneous parens
account.h: Removed nonnull attribute from function with no pointers
act.wizard.c: Removed gcc-specific nested functions
hell_hunter_spec.c: Removed unused variable
spec_procs.c: Rewrote check to remove ambiguity.  NPC thieves will
probably steal more from others.
Merge pull request #240 from dlowe-net/float-creature-weight

Creature weight is now tracked as a floating point value
Merge pull request #241 from dlowe-net/fix-clang-lint

Fixed more lint found by clang static analyzer
Added missing commands to the zset usage information
Merge pull request #242 from origintempus/Added-zset-usage-commands

Added missing commands to the zset usage information